Razor Floss



""The softest thing in the world dashes against and overcomes the hardest; that which has no [substantial] existence enters where there is no crevice.""

- Lao-tzu, Tao Te Ching

Razor floss is when any long, thin material -- string, thread, fine wire, etc -- is used as a weapon with Absurd Cutting Power. Odd as it may sound, strings can become deadly weapons in the right hands. Besides restraining enemies and even controlling other people's bodies against their will, or triggering traps, they can be pretty handy for cutting. In many works of fiction, one skilled enough, can use strings to cut opponents or even boulders, without hurting themselves. Naturally, monsters of the humanoid arachnid variety can usually be counted on to be using this trope.

Fantasy settings generally have this type of string made of human hair, while in more modern ones it's probably monofilament wire. In series less reliant on the Rule of Cool, the wire usually manifests as garrotes or tripwires, with varyingly messy outcomes.

What the audience sees usually amounts to Sword Lines sans the sword. Can be counted on to inflict an absurdly Clean Cut on its victims.

In reality, cables and metal wires can be used to inflict not so clean but still pretty nasty wounds, provided they are of the right material and/or sufficient force is applied.

Compare Whip Sword and Killer Yoyo. Subtrope of Absurd Cutting Power.

Anime and Manga
"A random cop: Get forensics down here ASAP. Uh, someone who's good at puzzles..."
 * The titular character of the Boogiepop Series wields this quite efficiently and lethally.
 * Walter C. Dornez of Hellsing is a prominent example. With ten monomolecular filament wires, he can obliterate armies of the undead.  he can slice buildings to pieces and mesh his wires into barricades. He also takes up puppetry.
 * Yashamaru of Basilisk.
 * Yura of the Hair from Inuyasha.
 * Gein from the Rurouni Kenshin manga.
 * (Filler) A team of two villainous brothers in Rurouni Kenshin did this so well that the local townspeople thought they were using magic. Kenshin defeated them easily once he recovered his sword- he just cut the strings off.
 * One episode of Cardcaptor Sakura had Eriol manipulate Shaoran like a puppet using well-placed strings, much to Shaoran's horror. This is also stopped with Sakura using the Sword card.
 * In X 1999, this is the way Particularly egregious since it's done with electriclal wires taken from a street post, which are considerably thick.
 * One of Ranma's enemies uses this. It's amazing how much of his clothes get cut by the closing loops, but how little of his SKIN actually breaks.
 * That's because the movie obeyed the basic notion that Ranma martial artists are Made of Iron.
 * There's also the fact that, unlike most examples of this trope, the wielder wasn't able to exert the force she needed to pull the strings tight enough to slice through flesh. That was why she made that big deal about twanging the strings; the tightly wound strings, vibrating in response to being stroked, generated the force to cut into Ranma's flesh and couldn't hurt him otherwise. Her dramatic strumming of all the strings simultaneously would have carved Ranma into chunks if Shampoo hadn't cut the strings before the vibrations reached him.
 * Though wouldn't that mean it would have done nothing at all if he'd taken even one step forward, thereby producing slack, instead of pulling back on them and making them tauter, like actually he did?
 * Nobody ever accused Ranma of being a genius. However, it's probable the wielder would have likewise taken steps back to tighten them.
 * For those who don't like obscure references: the character was Mon Lon of the Shichifukudojin (or, in dubbed English: Seven Lucky Gods Martial Artists); the movie was Big Trouble in Nekonron, China. And the whole scene was a parody of the fight with God Warrior Mime in the Asgardian arc of Saint Seiya.
 * The three Gamia sisters of Mazinger Z. They are three identical, long-haired, human-looking robots. Each hair strand of theirs is sharp and can cut through blocks of stone. They showed up again in Mazinkaiser and Shin Mazinger.
 * Bishonen Benten from Cyber City Oedo 808 used this as his weapon of choice, slicing through bad guys quite stylishly.
 * Kazuki from GetBackers (pictured), who's also known as "Kazuki of the Strings." They're just ordinary koto strings (harp strings in the Tokyopop version) that defy the laws of physics because of the vibrations he applies to them with his fingers. The picture above is actually a relatively tame example; in the last arc of the story, he destroys multiple skyscrapers in seconds with his strings. Other characters who use strings can also create perfect body-doubles of themselves, tigers, and supernatural cocoons attached to the heart.
 * Razor Floss is one of Amagumo/Rain Spider's many, many weapons in Desert Punk. He even compares it to a spider's web.
 * Nao in Mai-HiME and Mai-Otome.
 * The garrotte wire used by Yoji in Weiss Kreuz occasionally functions as Razor Floss, although much more often he simply strangles or restrains people with it.
 * L.A. from El Cazador de la Bruja is freakishly efficient with this weapon.

"Alice: It's puppeteer's thread... you'll only cut yourself if you try to struggle... so please be a good doll and stay still..."
 * Chocolate from Sorcerer Hunters is yet another user.
 * In the anime, Chocolate's weapon is less the wire and more the long, thin needle attached to it; in the manga, it's straight Razor Floss, with some attention paid to its physics in a few chapters-- it can stretch to incredible lengths and is highly conductive to electricity. Tira has a spool of it, and at one point uses it to marionette an entire casino hall, resulting in Tira winning a fortune in cheated winnings and the pit boss ending up as party cubes.
 * One early case in Majin Tantei Nougami Neuro involves a decapitation via wire attached to rubber, making a "guillotine slingshot", as Neuro puts it.
 * The main weapon of Elf and Zwolf in Battle Angel Alita: Last Order usually in tandem. They've used it for defensive traps,deadly "cat's cradle" attacks,helping with Sechs' Fastball Special and... knitting a scarf supersonically in the middle of a tournament. .
 * This is a standard weapon of some ninja in Naruto, though it's rarely used to cut anything, just to restrain opponents and Sasuke has used to it redirect projectiles.
 * Chiyo's puppets of Sasori's parents (formerly owned by Sasori himself) play this straight, as their hands are attached to each other by wires that can easily cut other puppets by wrapping around them.
 * Lyserg's dowsing pendulum functions as this, when the crystal at the tip isn't being used as a homing dagger.
 * Evangeline of Mahou Sensei Negima likes to use this like People Puppets. She says she can control a total of three hundred people simultaneously within a three kilometer radius (long wires!). She of course uses Hermetic Magic to help.
 * As stated above, Saint Seiya, the Asgardian God Warrior Benetnasch Eta Mime, wears a Cloth reminiscent of a harp. As such, he is prone to laying down Razor Floss around the environment as traps, as well as send them flying towards his opponents to entangle them. Note that his harp's strings are strong, and sharp enough, to crack and cut through solid rock, as well as Bronze Cloths and the very human skin of the Saints wearing them.
 * In the Rumiko Takahashi story Mermaid's Scar, Creepy Child Masato strings up piano wire at knee-height to trip the immortal Youta, and, hopefully, slice his head off. Youta receives cuts on his shins and a particularly deep gash on his neck, but is otherwise okay.
 * One character in Bastard!!!! has this as a main weapon
 * Triela makes use of one of these to strangle a guard in an episode of Gunslinger Girl.
 * Belphegor of Katekyo Hitman Reborn combines this with Knife Nut by attaching wires to each of his thrown knives.
 * Jenos Hazard from Black Cat has a glove with lines of Razor Floss attached to the tips of the fingers as his primary weapon.
 * Keep in mind, he belongs to an assassin organization whose members all have weapons tailor-made to their abilities, made of an indestructible metal alloy.
 * Gundam X has a Mecha Of The Week named Britova whose weaponry includes a rocket-guided razor wire. The universe's backstory also has a Gundam Belphagor (no relation to the above) which uses several wrist-mounted wires to defend against Attack Drone-type weapons.
 * Before he became a ninja, Dororo of Keroro Gunsou was a deadly assassin and this was his trademark weapon.
 * In the Touhou H-doujin Ningyou Kakumei, Alice manages to trick the naive doll Medicine into consenting to helping her in her research to make a self-capable Doll. As soon as Medicine said that she'd help, Alice traps her with puppeteer's threads:


 * In Trigun, Vash the Stampede occasionally ties a string to his gun in the anime format, allowing him to retrieve it quickly if disarmed and also, with some simple pulley mechanics, to fire on an enemy from a different angle than the foe expects. In the manga format, Leonof the Puppet Master also uses invisibly thin strings to control his hordes of killer marionettes (in the anime, he apparently just uses remote control). Finally, Legato's ability to control the bodies of his enemies is revealed to work by means of microscopic threads which infiltrate the nervous system and manipulate it by means of electrical pulses.
 * Leonof did use wires in the anime; that was where Vash got the idea for the wire-trigger trick.
 * Jubei of Ninja Scroll keeps his sword wired, so that he can retrieve it quickly. One of the villains also uses wire, mainly as a communication device (similar to a cup-and-string getup), as well as a means to electrocute people.
 * The Ordeal of Strings during the Skypeia arc of One Piece.
 * This also seems to be an application of whatever power Donquixote Doflamingo has which he used to cut off both Oars Jr.'s leg and Crocodile's head. Presumably he uses the same strings for his People Puppets skill too.
 * A frequent murder weapon in Detective Conan -- in fact, the first case solved involved a beheading on a roller coaster using monofilament wire.
 * The first Appleseed movie had a pair of gynoids with cutting whips that did quite a number on Hitomi's car and later on Briareos' Hand Cannon as well.
 * Word of God for The Slayers is that the Crown Princess of Seillune, Amelia and Naga's mother, created a spell called "Chaos String" that allows the caster to manipulate threads. Word of God also states that Naga used this spell to kill an assassin that murdered her mother, and that Naga has been terrified of blood ever since.
 * In To Aru Majutsu no Index, Kaori uses this to simulate super fast sword strikes.
 * In Ironfist Chinmi, one of the many evil Kung Fu masters that the titualar character fights uses this weapon as part of his style. Using a single strand of razor floss, he whips it at a target so that it coils around the target's limb, then pulls on it so that it unravels with such speed it cuts flesh. A fairly realistic portrayal in that it only works if he can strike a foe from the side with it- though he is skilled enough with it that, straight on, he can still inflict minor gashes or use it to pierce like a needle.
 * Little Boy in the Spriggan movie uses this briefly to render mook guards into chunks.
 * In Hunter X Hunter, Machi a member of the Phantom Troupe, is this. She spins her aura into threads in which she uses in a variety of ways, including seaming together dislodged limbs, attaching strands to people in order to track their movement, and as a weapon.
 * Mouse's arch-enemy One uses lots and lots of this as his weapon of choice.
 * In an episode of Yami no Matsuei, . Not only that, but  YEOWCH.
 * Surprisingly enough, this appears in Haruhi-chan. Yuki uses it to restraint a mutant Santa Claus.
 * Chiaki from Kamikaze Kaitou Jeanne uses this near the end.
 * Rika from Shikabane Hime has a clawed glove that also has razor floss.
 * Kubinashi from Nurarihyon no Mago uses razor floss as his weapon of choice.

Comic Books

 * Diamond Lil, from Alpha Flight, sometimes plucked a hair from her head and used it as a slicing garrotte. Justified by her being Nigh Invulnerable, over six feet tall, and very, very strong (thought not superhumanly so). Since it can't be cut, her hair is also very long.
 * John Byrne loves this idea, he did the exact same thing with the invulnerable Hardbody from Next Men.
 * And if memory serves he did an issue of Fantastic Four where Doctor Doom trapped She Hulk in a cage, the "bars" of which were so thin they sliced into her arm when she tried to push against them.
 * In Top Ten,.
 * Super-Skrull pulled this off in the Annihilation Mini he received, stretching his body like Reed Richards, but keeping it Thing durability. Razor wire.
 * The Batman villain KGBeast kills a key member of the "Star Wars" missile program this way, hanging wire across the street down which the victim motorcycles. The victim's head is sliced clean off.
 * In the Andrew Vachss series Cross, Cross and his crew escape from a juvenile detention center using dental floss to cut the bars on one window. They also dipped to floss in comet cleanser to provide an abrasive. This took some time, with strong guy Rhino chugging away at the floss and Cross reading him poetry to keep him motivated.
 * This is actually possible. There are a couple of real life examples of breakouts where prisoners cut through bars with dental floss.
 * The Indigo Prime story Killing Time featured one of the protagonists using a harp - however, the strings weren't sharp enough to slice effortlessly through the flesh and needed him to be forced through face first. The fact that harp strings could be strong enough to not only resist breaking but also slowly carve through flesh and bone can be handwaved by the fact that.

Film
"E.L.F.S. Leader: Tinsel. Not just for decoration."
 * Grids of such wire are used in the Cube Series to kill off the first character we see in Cube. Many traps in the movie are like this.
 * In the film version of Force 10 from Navarone, Force 10 used the old "wire strung across a road" trick to decapitate a Nazi officer.
 * One of the Predators from Alien vs. Predator used a weapon that fires a net which somehow manages to cut into a xenomorph's head leaving a net patterned scar through the rest of the movie.
 * I believe this first appeared in the second predator movie. Basically, the net is made of thin wire and it tightens, cubing the person it captures. I suspect that the xenomorph blood burned it away after it first penetrated.
 * A support wire is used for just the first part of the mass murder in the opening scene of the horror movie Ghost Ship.
 * The magic tinsel employed by the elves to break Tim Allen out of jail in the first The Santa Clause.


 * In the film adaptation of Johnny Mnemonic, the yakuza assassin's monofilament whip is attached to a giant gold thumbnail rather than the whole digit. It also glows like some sort of laser-whip.
 * A famous scene in the Australian cult classic Stone involves the murder of a biker by a high-tension wire, followed by his head rolling along the road.
 * Audition. Asami Yamazaki cuts off body parts by using piano wire.
 * In Final Destination 2 a character is trisected horizontally by a flying wire fence.
 * Men of Honor: In the same vein as many of the listed Real Life examples, Cuba Gooding Jr's character suffered an accident where a large cable snapped, whipping around and injuring his lower leg.
 * The Three Musketeers 2011 had a trap made out of Razor Floss that effortlessly sliced a dropped ribbon into several pieces, filling the dramatic purpose of a Laser Hallway.
 * In Piranha 3DD a character is decapitated by perfectly normal bunting at neck height when he drives a jeep not particularly fast into it - though given the nature of the film the absurdity is certainly intentional.

Literature
"Mitth'raw'nuruodo: I knew the spacecraft would come to search. In preparation, I had strung some of my monofilament line between two of the taller treetops. One of the spacecraft hit it."
 * Poul Anderson's story "Thin Edge" (written under the pseudonym "Winston P. Sanders") appeared in Analog Science Fiction Magazine in 1963, possibly making it the Ur Example.
 * Monomolecular trip wires appeared in William Gibson's Count Zero. In the short story "Johnny Mnemonic," a yakuza assassin has a monofilament whip attached to the first digit of his thumb. When he pulls on his thumb, the filament extends and the joint becomes the weight for a whip that can decapitate his enemies with one swing.
 * The Dune series included monofilament "Shigawire"; mainly used in recording devices, it also served as a very effective garotte.
 * It's used instead of barbed wire around the robotic nursery in the novel version of Logan's Run.
 * It was used as a spaceship weapon in the Deep Space Nine novel Objective: Bajor, where the enemy ships flew out in pairs with a monofilament net between them. The net was so fine it couldn't be seen or blocked by shields, but any ship that was netted simply crumpled to atoms, occupants and all. They also had a net pulled by torpedo, for when the paired ships were split up.
 * There's also a scene in Stormbreaker where a pair of ATV's try to slice apart our hero with cheese wire in between the two vehicles.
 * There's a Chekhov's Razor Floss in Arthur C. Clarke's "The Fountains Of Paradise", made of the carbon filament formulated for the space elevator.
 * Larry Niven gives us a couple of examples:
 * Ringworld: shadow square wire
 * Also from Ringworld: a variable sword is monomolecular wire in a Slaver stasis field (making it rigid and essentially indestructible). Goes through metal like butter.
 * Sinclair Molecule Chain in A Gift from Earth.
 * The whole plot of The Descent of Anansi revolves around this.
 * Featured in a Tom Swift III novel, though I can't remember the name of it. Tom wore diamond-coated gloves to handle it. It was the one where they got shrunk.
 * This was actually in the Tom Swift IV novel The Microbots; while shrunk, the monofilament is thick enough to be safely used as a rope.
 * Carl Hiaasen's ''Skin Tight' features another low-tech implementation of this method, in this case using two trees and some fishing wire.
 * The early Orson Scott Card novel Wyrms has the heroine keeping a strand of this in her hair for use as a weapon in case of an assassination attempt.
 * In David Drake's RCN series, Daniel Leary's retainer, Hogg, experienced poacher, uses lead weights on the end of monofilament fishing line for striking, restraints, and once severed a hand from a wrist.
 * In one of L.E. Modesitt's Saga of Recluce novels, the heroes set up defenses involving razorfloss strung along paths down which the enemy cavalry would charge.
 * In Alastair Reynolds' Absolution Gap, one of the bad guys has an artificial hand with razor floss built into it.
 * In The City Who Fought by Anne McCaffrey and ~S. M. Stirling~, Joat, a young girl, sets up several strands of monofilament wire across a corridor than baits a Kolnari patrol to chase her, running into the trap. The Kolnari are literally sliced to pieces by the molecule-thick wire, making for a gruesome, bloody scene. As Joat says, it "...gives a new meaning to 'cut off at the knees!'"
 * The third episode of Dan Simmons' Hyperion Cantos, Endymion, features monofilament wire used as a tripwire in an ambush. It was also conveniently hidden in a spool of sewing thread.
 * The short story "Mist Encounter" has Thrawn running rings around the Imperials sent to investigate his place of exile, then calmly explaining exactly how and what he did to the captain. One of the many things he did was cause a TIE fighter to crash.


 * The Stainless Steel Rat encounters an assassin using monofilament wire, but only to lower himself to a balcony where his target is. Jim DiGriz, who's working as a bodyguard of the target, has to drop several stories onto the balcony to stop him, as an attempt to climb down the wire would slice his hands open.
 * From West of Eden and its sequels by the same author, monofilament knives are the standard cutting tools for Yilane (basically intelligent tool-using dinosaurs).
 * Brotherhood of the Rose by David Morrel. One of the protagonists is being garroted by a fellow assassin; it's mentioned that such wires are embedded with diamond so it can saw through fingers if the mark is able to get them in the way in time. This is what begins to happen, but fortunately he's able to break free before then.
 * Combat Drones deployed by The Culture occasionally use monofilament warps stretched between two remote controlled projectiles. The filaments seem capable of cutting through most conventional materials with no effort.
 * References abound in The Executioner series to guards having their throats cut open with piano wire garrotes, while monofilament trip wires were often mentioned in the Able Team series.
 * In Dan Abnett's Gaunt's Ghosts novel Salvation's Reach, the assassin used wire as a garotte.
 * In Diane Duane's The Romulan Way, McCoy's Romulan captors bind his hands with a ribbon with a monofilament at the center. It's perfectly safe if he doesn't fight it...and if he does, his hands fall off.

Live-Action TV
"Mainwaring: Instant decap- * wire snaps* oh."
 * In one episode of Dads Army Captain Mainwaring describes the use of cheese cutters as a garrotte, causing Private Pike to become ill. Sgt. Wilson suggests it's because Pike hates cheese, rather than Mainwaring's mention of decapitation.
 * Also notable as a subversion -- when Mainwaring actually tries to demonstrate the technique (on a dummy, if I recall correctly), the wire snaps and breaks out of the handle.
 * He just demonstrated the motion in mid-air and ended up pulling too hard.


 * In one Bones episode, the murderer was a sculptor who, driven to rage by his neighbour's singing, garotted him with a sharp wire he used to cut clay.
 * The "wire strung across the road" trick was used in a Midsomer Murders episode to decapitate a motorcycle rider.
 * And in a 1000 Ways to Die episode, "Golden Die-Angle", a drug enforcer is decapitated in the same way while riding an ATV.
 * An episode of Dark Angel had a police officer recount how some firemen got their throats slit by piano wire strung across doorways.
 * An episode of Angel had Angel and Spike pull this trick on a supposedly-unbeatable guardian.
 * Jerri relates a story on an episode of Strangers with Candy, in which a guy-wire slices Bongles the clown in two at the circus; leaving "two, small, dead clowns."
 * Andromeda had the M-lash, a molecule thin whip that was so sharp if you tried to set it down with out turning it off first it would cut through the table, then the floor, etc.
 * Dylan even comments on this questioning the intelligence of an opponent who would use such a weapon onboard a spaceship
 * The first episode of Foyle's War, The German Woman, involves a particularly cruel case of this. While out riding her horse, the titular German woman hits a length of wire strung between two trees at neck height. Foyle kindly explains to us later that - unfortunately for her - it doesn't result in complete decapitation, and she is simply left to bleed to death on the ground.
 * Renge in Kamen Rider Kabuto uses this as her signature weapon.
 * In Boardwalk Empire, a gang enforcer garrottes another man with a wire cutter. While he has to use much more force than usual for this trope, he does manage to garrotte the man through his fingers, leaving them severed on the floor.

Tabletop Games
"1032. Monofilament does not automatically make the world a better place."
 * Shadowrun (and Cyberpunk 2020) had monofilament swords and whips and used monofilament in traps. Judging from the hacker chatter in some of the Sourcebook, though, the monofilament whip is looked at as something of a fool's weapon, since an untrained user is as likely to decapitate himself as his enemy. This never gets reflected in game rules, of course, although it does suggest a truly evil result when the "Rule of Ones" comes into play.
 * The 4th edition of Shadowrun does give explicit rules for what happens when someone botches a monowhip attack. It's pretty nasty.
 * This is, however, made up for by the fact that the Monofilament Whip is arguably the single best melee weapon to use against an armored opponent due to it having excellent damage, long reach, and very good armor penetration.
 * One of the sourcebooks also made fun of the use of the term "monofilament" with the chatter at the bottom of the monofilament sword entry commenting that his shoelace is monofilament (one piece) too, but it doesn't cut through anything.
 * Specifically, it pointed out the difference between any old monofilament, and a monomolecular monofilament. Much of the gear in that particular sourcebook fell into either the Awesome but Impractical or completely foolish categories.
 * In 3rd Edition, whips (including the monofilament variety) had a chance to strike the wielder if the target dodged (rather than the wielder just missing).
 * The Eldar of Warhammer 40000 are fond of monofilament wire, and apply it to their enemies with many creative ways, such as forming clouds out of it, or unfurling a spoolful of it inside an enemy.
 * List of Things Mr. Welch Is No Longer Allowed to Do In An RPG (1001-1250) reminds us for a reason that


 * In TSR's short lived RGP, Alternity, there was a particular type of villain named the "kroath" who made use of monofilament wire to set up traps. On a good roll, the material was capable of killing PCs in one attack.
 * GURPS finds a bunch of clever uses for monowire from whips to swords to fences to bullets. There's also a superior version called nanothorn which is like monowire but doesn't cut things so much as it dissolves them.
 * Dungeons and Dragons
 * Crystal spiders from Dark Sun make glass webs that are razor sharp, near-invisible, very strong and entangling (though not sticky as such) at once.
 * The spider-like Head Hunter in Ravenloft spins webs of this stuff--usually right at neck level. Being so thin, they're near-invisible...

Video Games

 * Kurenai, from Red Ninja: End of Honor uses a tetsugen, or an iron wire.
 * Sion's Etherite from Melty Blood is not only used as a Razor Floss weapon, but can also be inserted into people's nervous systems to allow her such abilities as reading their thoughts and controlling their bodies.
 * Sima Yi in Dynasty Warriors 6 uses this as his primary weapon, ostensibly to symbolize his Puppet Master tendencies.
 * Agent 47 from the Hitman series has a garrotte wire as his second signature weapon. It does not leave blood unlike knives, and is the best weapon to use as a Silent Assassin.
 * Manhunt also has a barbed wire garrotte.
 * Harp Note has this as one of her attacks. After binding you with her guitar strings, she riffs a few times. It hurts.
 * Syndicate Wars. Being the classic monofilament stuff, Razor Wire is really hard to spot and is laid down as traps in alleys to hamstring unsuspecting runners. Its badder brother Trigger Wire is as difficult to notice and supposedly adds explosions.
 * Marcy from Chrono Cross utilizes string-based attacks as her techs, for cutting, sending energy bursts through them and even shifting earth.
 * Kasuga from Sengoku Basara uses these along with Rings of Death.
 * Sonya Blade utilizes this as a fatality in Mortal Kombat 9.

Webcomics

 * Captain Tagon from Schlock Mercenary has a "Dorothy System" in his boots. He clicks his heels together, and it strings a mono-wire between them. This makes a dandy surprise weapon. He's used it to disarm Schlock - literally (he got better). He later uses it to decapitate Elf so that he can put her head into suspended animation and get her safely back to the ship before his last stand in one of the Schlocktoberfests.
 * Supposedly it was named for Dorothy's magic slippers. She would click her heels together and say "there's no place like home." With this weapon you need not say anything, although users do tend to say things like "eewww".
 * Subverted in this B Side Comic from Sluggy Freelance.
 * Reginald Jeeves (yes, you read that right) in And Shine Heaven Now: in fact, he was the one that taught Walter how to use them.
 * Butch from Chopping Block has some fun with wires on a ski slope.
 * Never Mind the Gap has living monomolecular wire. It was introduced cutting off a robot's metallic fingers.

Web Original

 * SCP Foundation-]]183.

Western Animation

 * The Simpsons had an episode where Snake (the convict guy) tried to kill Homer by setting up a fine wire across the road as Homer drove past in a Sports car. He only succeeded in cutting off Kirk Van Houten's arm.
 * Truth in Television, as he was using piano wire, which is strong enough that something hitting against it like Kirk's arm at that speed would be severed in a cutting fashion.

Real Life

 * The low-tech "wire strung across the road" trick was a means of guerrilla warfare in times when most officers and messengers went about at high speeds on horseback. In many versions of the Headless Horseman myth, this is how the Hessian mercenary that became the Horseman originally lost his head. Later it would find use in World War 2 on soldiers of both sides riding either motorcycles or open top vehicles like Jeeps. This trick was also taken up by the IRA during The Troubles.
 * If you look in better done movies or old war films, you'll see an A-frame device on the front of jeeps and such. Those were used to cut wires by channeling it up into a cutting notch. There are similar devices on modern helicopters as well.
 * As well as in wire-on-parachute shells and cables of anti-aircraft balloons.
 * Also a danger in the Florida Everglades and other swampy areas in which barbed wire has been strung across an area. Most of the giant fan-driven swamp boats will have a cutter in the front to prevent unanticipated decapitations.
 * Razor wire, a more advanced version of barbed wire, is used in trench warfare to stop infantry movement. It is still in use to prevent people from climbing fences, or to prevent cattle from trying to get through a fence.
 * Partial Truth in Television: British secret agents during WWII were rumored to use so called Gigli saw -- a thin, flexible wound-wire saw with embedded diamond or corundum dust, widely used in surgery for bone-cutting -- as a shoelaces. Very similar in thickness and construction to a piano string (it could be substituted by the one in a pinch, in a matter of of fact), it could be easily used for garroting, but just pull it by one side -- and Off with His Head!
 * Still, less painful than the movie Gigli.
 * Arguably. The Gigli saw wouldn't give you a couple of all-to-brief moments of respite with Christopher Walken and Al Pacino, though.
 * Cheese cutters. They can do a lot more damage to non-cheese materials than you might think.
 * Any wire, or even occasionally rope on a ship is a potential case of this. Get your arm tangled in a spool of wire attached to something heavy - say, a sail or fishing net - and lose control of it and… rrrrip. This can strip flesh to the bone - or even in some cases strip limb from body.
 * Even worse, high tension cables, chains and ropes that snap in industrial accidents. Since they're designed to withstand many thousands of pounds of stress, all that energy goes directly into both halves of the line, which can also weigh hundreds of pounds by themselves, whipping chaotically to strike or slice clean through anything within the arc circumscribed by their unspooled length around their anchoring points.
 * Ditto the arresting wires on CATOBAR aircraft carriers. They are inspected daily. Having one of them snap is a very bad thing.
 * During the filming of the unfinished Gone in Sixty Seconds 2, a cable that was supposed to pull down a water tower snapped and felled a telephone pole, fatally crushing filmmaker H.B. Halicki.
 * The Italian mafioso Vincenzo Curcio escaped from prison in Texas by sawing through the bars with dental floss. This was possible because the bars were made of iron low in carbon, which was easy to saw through.
 * IIRC, he also used tooth powder (an abrasive that used to be more commonly used for dental cleaning) on the wire, increasing the grinding power.
 * The Indian chuttuval, the IRL Whip Sword, is basically made of flat, sharpened wire.
 * It's really more like a long band-saw blade.
 * You can supposedly spot deep sea fishermen who've carelessly wrapped the line around their hand when reeling in a big fish. They're missing fingers.
 * That's why archers' equipment includes bracers (and protection for fingers, in some styles): no one wants to be flayed by moving string.
 * The infamous "hilo curado" ("charged string") used in Chile to have kites fly and cut each other's strings. Basically, it's normal kite thread covered in liquid glue and pulverized glass. Dangerous as hell. In Brazil it is called "cerol". People die: onlookers, participants, people who are just in the wrong place at the wrong time. This style of kite combat is actually fairly common all over the world.
 * The novel The Kite Runner focuses upon them a lot in the first (and in the last) chapters.
 * It was so bad in Brazil a few years ago, that the electricity company had some ads against it. Because it can cut through the thick wires and kill the kite flyer electrocuted.
 * This is basically the theory behind the rope saw.
 * Simple monofilament fishing line, the stronger types in particular, can certainly be used like this (intentionally or otherwise). In addition to the above examples, it can also be used like a rope/wire saw (and can cut through PVC pipe, in fact). And for those fishermen stranded in the wilderness...strong, nearly-invisible line is perfect for making snares to catch a meal. Just don't forget where you left the traps.
 * It's worth mentioning carbon nanotubes. The longest ones are 18cm long right now, but they're getting longer and cheaper all the time. One tube has a width of only a few nanometers, and the bonding used to hold the tube together means that the tubes are harder than diamond and have a higher tensile strength than almost any other material. Also, given its structure, it really is a true monomolecular filament; application of proper force would let one slide through just about anything like a hot knife to butter.
 * The winch cable they use to launch gliders can be quite dangerous: a kilometer long cable moving at high speed, there are stories it cut a cow in two, unlucky enough to wander on the airfield. The cables have a parachute at the end so that they fall gently after being disconnected from the glider after takeoff. If the cable breaks during takeoff, it can snap to the ground with great force, so the winch itself is usually armored or at least has reinforced bars on the windows.
 * Executing a man by hanging is actually a tricky procedure. The rope selected for the execution must be carefully calibrated to the weight of the condemned - otherwise, the hanging could accidentally become a decapitation instead. This has infamously happened to the western outlaw Tom Ketchum.
 * Similar to the industrial cable example above: nylon mooring lines (the ropes used to tie ships to a pier) are extremely dangerous if pulled too tight. Nylon can strech quite a bit and if the line snaps it will go whipping across the deck, easily killing or dismembering anyone in its path.
 * Not a rope or a cable, but have you ever being cut by the edge of a paper sheet?. It's hard that it occurs (at least intentionally), but when it happens is quite painful.
 * Even lighter strings are capable of cutting. As a maintenance worker, I used to cut in-ground PVC pipes with a length of standard twine. Sliced my own finger once when I got careless...