Bizarre Alien Locomotion

""The sheer number of creature possibilities is staggering, and it's impressive how you can give them eighteen legs and seven eyebrows and it'll still somehow find a way to walk and make suggestive poses.""

- Zero Punctuation, Spore

Thousands of species of Real Life organism move by walking, swimming, or flying with wings. Most Speculative Fiction species do the same. But whether to showcase the physical demands of a creature's unusual habitat, to prove it can be done, or merely to make them stand out in a crowd, writers sometimes dream up truly weird ways for their creations to get from point A to point B. Wheels are a common example, possibly for the sheer absurdity of the image.

This trope is not intended for teleportation, plane shifting, and other means of travel that break the laws of physics. (Bending those laws is acceptable, however.) Bizarre technological methods of locomotion belong under the various vehicular tropes.

Subtrope of Bizarre Alien Biology. Supertrope of Heli Critter.

Rollers

 * In The Amber Spyglass, the Mulefa clutch giant seed pods in specialized gripping appendages and roll around like living motorcycles.
 * One of the alien races from the Cluster series roll around on a single large sphere embedded at the bottom of their tear-shaped bodies.
 * IIRC there's also a species that rolls on disc-shaped projections from its cylindrical body.
 * Wheelers in the Land of Oz have wheels instead of hands and feet and locomote by rolling around on them.
 * Lexx: Cluster lizards have long flat segmented bodies and roll into hoops that can roll rapidly. They're also predators, so you don't want to get in their way. When Zev/Xev accidentally acquires Cluster lizard DNA she also acquires the ability to curl up and roll fast, though it's not demonstrated until season 3.
 * The mythical "hoop snake" of folklore moves the same way, holding its tail in its mouth and rolling like a wheel.
 * M. C. Escher's lithographs "Curl-Up" and "House of Stairs" feature creatures called "curl-ups," which resemble metallic caterpillars with plated bodies and can either curl up and roll, or walk around their weird environment on six humanoid legs.
 * Pangolins do this in Real Life, aside from having only four legs instead of six.
 * In David Brin's Uplift series g'Keks have wheels.
 * The Lensman series book Galactic Patrol. The inhabitants of Aldebaran I are the Wheelmen, who are literally wheel-shaped aliens, like a living example of Monowheel Mayhem. As you might expect, they move by rolling around like wheels.
 * The cover art for The Science of Discworld III shows men riding on a giant tortoise with wheels in place of its feet. This was probably created by the God of Evolution, who'd been working on a wheeled elephant when he'd previously appeared in The Last Continent.
 * Before it became its own theme, Bionicle offered some weird machine-animal mixes under the LEGO Technic logo: the Tarakava and Tarakava Nui lizards, Muaka tiger, Kane-Ra bull, Kuma Nui rat, Manas and Mana-Ko crabs are all creatures that had tank threads for back legs. What's more peculiar is that in the story, everyone regarded these as having honest-to-goodness legs.
 * On the original Ben 10, Ben's Kineceleran form XLR8 has small black wheels on both feet. His Petarola form as Cannonbolt can curl into an armored sphere and roll at high speed.

Other Ground-movers

 * Alan Dean Foster's Icerigger trilogy features the Tran, a race of ice world natives with claws on their feet that act as natural ice skates, and sails beneath their arms that let them catch the wind for propulsion.
 * The Skiapods from Greek Mythology have one giant foot at the center of their bodies, so move about with tremendous jumps.
 * The Dufflepuds in The Voyage of the Dawn Treader are inspired by the Skiapods.
 * As is Sukiya Podes in Puyo Puyo series.
 * As is Munch, the last surviving Gabbit in Munch's Oddysee
 * Real Life example: Sidewinders are desert snakes that crawl rapidly across the sand by throwing loops of their own bodies ahead of themselves.
 * Another Real Life example: Springtails, tiny close relatives of insects, have a long springy appendage under their bellies, which they can release to hurl themselves into the air and escape from predators.
 * Star Wars:
 * Kitonaks move by extending and contracting their toes. It's very slow, but then again Kitonaks are never in a hurry.
 * The Dugs from Star Wars walk on their hands, while using their feet as... well... hands. Not sure if this qualifies, but since the things they walk on are specifically stated to be their arms and hands I'd guess it does.
 * Like the Dugs above, night stalkers from the future-evolution book After Man a Zoology of The Future walk bipedally on their forelimbs, while fighting with the long claws on hindlimbs that reach forward. Justified in that they evolved from bats that became flightless due to isolation on an island chain, so their forelimbs were the only ones strong enough to walk on.
 * Web Comics: One of the species in Unicorn Jelly and spinoffs has a tube-shaped body with a foot at each end, and they ambulate by placing one foot on the ground and then arching over to place the other one, etc. Leeches crawl and climb in a similar fashion in Real Life.
 * The Rhinogrades from the Mockumentary Snouters are a groups of fictitious mammals, some of which walk on their multiple nasal trunks.
 * On an extraterrestrial life-themed episode of Into The Universe With Stephen Hawking, one of the hypothetical creatures shown is an herbivore with two legs and a huge suction-cup mouth. Using the latter, it could walk up and down vertical cliff faces.
 * At one point in John Carpenter's The Thing, a piece of the alien uses an elongated tongue to drag itself along the floor.
 * Dominic, a greyhound that lost both right legs when he was hit by a car, manages to stand, walk, run and even jump on his two left legs: an arrangement never seen in nature.
 * Wayne Barlowe's Expedition features an alien that hops around on one leg.
 * Most of the animals featured in the book have bizarre ways of locomotion. For example, the Flipstick is a 60-meter long pole-like creature that moves by flipping itself on both ends. The Gyrosprinter is a two-legged animal with one leg in the front and the other in the back (not unlike the Dominic example above). It supposedly evolved from a four-legged ancestor and both of it's front legs and back legs fused together. There is another creature that starts out with four legs but the hind legs atrophy as it matures and it's hind skid develops.
 * Oddworld literally breathes this trope, with several species (Sligs, Glukkons, Gloktigi, etc.) walking on their hands, and that's only scratching the surface.
 * Tigger from the Winnie the Pooh stories is depicted bouncing around on his spring-like tail in cartoon adaptations.
 * The Future Is Wild has a few odd creatures, such as the Megasquid: A terrestrial squid that moves around on eight modified pillar-like tentacles (Which have no bones like an elephant's trunk). It moves with a gait not used by any living animal today: moving its first and fourth legs on one side in unison with the second and third legs on the other side.
 * One hypothetical desert creature from the "Alien Faces" episode of The Universe had pillar-like legs anchored to a flat, scaly base that could slowly glide over sand.

Flyers & Floaters

 * Alan Dean Foster likes this trope. His Midworld and Mid-Flinx include many alien animals that drift in the air with helium bladders, while squirks -- tiny swamp reptiles from the Spellsinger series -- use four rotating props to hover like helicopters.
 * Meteos:
 * The inhabitants of Forte (Faulte in Japan) move about by leaping high into the air and using their parachute-like bodies to slowly descend.
 * Planet Bavoom seems to be a gas giant, so the creatures on it just drift around the planet's powerful winds.
 * One of the Ages from Uru: Ages Beyond Myst has disc-shaped creatures that spring up into the air and drift down like parachutes, similar to the Forte creatures listed above.
 * Battle for Terra - The aliens can fly and use their tails in a fashion similar to how fish use their tails to swim underwater.
 * Jetdarters and Skewers, in Expedition, use jet propulsion. The former are bug-sized, the latter are... jets.
 * Also used in Tremors 3, with he jet-propelled Assblasters.
 * Used by another race of Cluster series aliens.
 * In After Man a Zoology of The Future, the juvenile parashrew grows a parachute made of hair on the tip of its tail, and uses this to catch the mountain winds, dispersing over distances such a tiny animal couldn't otherwise traverse. The parachute-hairs fall out once it finds a territory of its own.
 * In Alien Planet, the last life forms encountered by Ike the probe are able to hover using large bags of methane gas.
 * The fan lizard from Avatar.
 * Keelerak spiders from Bionicle could fly by spinning in the air like a Frisbee, using their pointy feet to become giant buzz-saws. There are also shore turtles, which are simple turtles, that can, for whatever reason, fly. Though it's never explained how -- they don't have wings or thrusters.

Swimmers & Skimmers

 * Real Life: Squid and octopuses can use jet propulsion, squirting water out their siphons to quickly move forward.
 * There's the Real Life basilisk, also referred to as the "Jesus Lizard", which can run on water for short distances if it builds up enough speed and rises up on its hind legs. On land, it's just a regular lizard.
 * Water striders are insects that can also walk on water, distributing their slight weight far enough for surface tension to support them.
 * In The Future Is Wild, the ocean phantom is a colonial jellyfish-relative that drifts on the surface, using tall flaps of tissue to catch the wind and sail from place to place.
 * In Small Favor, Dierdre forms her animated blade-hair into a shark-like tail for swimming with when she dives into Lake Michigan.

Most Bizarre

 * Meteos:
 * Globin is a planet-sized living thing; it has an intelligent, sentient civilization comprised of leukocytes traveling around Globin's bloodstream.
 * The people of Wiral are made of electricity. They normally just float about but prefer to do high-speed travel through electric wires.
 * H.P. Lovecraft's Elder Things from At the Mountains of Madness could somehow travel through outer space using their fan-shaped wings. The original text depicts them flying through the aether, but Fanon insists that their wings are biological solar sails.
 * In Ghost Story, wraiths that aren't under the direct control of a more powerful entity are described as drifting ethereally through Chicago's ghost-realm, just barely out of contact with the ground, occasionally touching down with their toes to push themselves along. When commanded, they fly freely, suggesting that it's simply their lack of individual willpower that hinders their independent motion.