Ghost Memory

"Sharon/Athena: Just being with you and Kara feels like I've come home. It's like I'm back in the fleet.

Helo: But you were never in the fleet. That was the other Sharon.

Sharon/Athena: I know. I know that. But I remember all of it. Like getting my wings. My first trip aboard the Galactica. You know, the memory of being in a uniform is so strong, is so potent, it's, like, I'm Sharon Valerii and this is my family. That's pretty weird, huh?

Helo: That's okay. I like weird."

- Battlestar Galactica episode 207 "Home, pt 2".

A character gets others' memories or abilities through some external means, like magic or... ghosts. Compare with Genetic Memory, which uses genetics, reincarnation, and whatnot. Or Fake Memories, in which the implanted memory is totally made up.

Anime

 * A rather creepy part of the first Ghost in the Shell film. No, you have no ex-wife, or daughter. A hacker put them in your brain so you would do his bidding.
 * Perhaps even more disturbing is the moment in which he is asked to look at the photo he kept trying to show his coworker of his daughter and it turns out to be a photo of him and his dog.
 * Used by Gartlant (Yeah, I don't get the name either) in Saber Marionette J. Each fuhrer gets the memories of his predecessors impressed on him by a machine. It's not a pleasant process, and turned the current Faust from a normal kid to a vicious bastard who mistreated Tiger, Panther, and Luchs/Lynx from that day forward.
 * Immortals in Baccano inherit the memories of any and every immortal that they kill by "devouring" them. How much they affect you depends on the person -- Firo copes with having the memories of a three hundred-year-old Mad Scientist and eighteen of his victims by simply insisting he's too dumb to remember or make sense of any of it, . Czeslaw, on the other hand, doesn't handle it quite so well...
 * While Firo has the memories of a bunch of strangers running through him, Czes picked up the ghost memory of his beloved guardian, who spent upwards of 200 years gleefully torturing the kid under the completely false premise of "For Science!". It's basically Amnesiac Dissonance leading to a(n even more) Broken Pedestal, only the memories he recovered weren't his own.
 * The Lucifer and Biscuit Hammer: and himself appears when those abilities finally come into use.

Comic Books

 * Marvel Universe limited series Kitty Pryde and Wolverine. The evil Ninja Ogun tries to take over Kitty Pryde by impressing his mind on hers. Among other things, this gives her knowledge such as the ability to perfectly prepare a Japanese rock garden.
 * Absorbing people's memories is one side effect of Rogue's powers in most X-Men continuities, as well.
 * In The Sandman.
 * In Starman
 * In the DC Universe, This is how the legacy of the Great Ten's Accomplished Perfect Physician works. Each new holder of the title inherits the collective memories of their predecessors; the current one is the seventeenth, giving him sixteen lifetimes of experience to draw on.

Film

 * In the eminently forgettable Ray Liotta film Unforgettable, A doctor, accused of the murder of his wife, injects himself with her memories, or some damn thing.
 * In Total Recall, people of The Future typically take vacations by having the memory of an exciting trip implanted in their brains, rather than by going on an actual trip somewhere.

Literature

 * In Frank Herbert's later Dune series novels, the Bene Gesserit have the ability to share memories by using their mental disciplines. Some of them have the combined memories of a planet's worth of their fellow Bene Gesserit.
 * In the novel Green Rider, Karigan is briefly possessed by a dead swordsmaster and fights another swordsmaster to save her own life. Later, the moves and skill he used is available to her, making her a better fighter than before.
 * The Sword of Truth: Richard channels the skills of the titular sword's previous users in order to defeat a large group of master swordsmen.
 * The Wheel of Time: a wish, and the wishgivers responded by filling his head with spare memories of other people who had visited them. . He also demonstrates cases of Genetic Memory early in the series.
 * Terry Pratchett's A Hat Full of Sky, a Discworld novel, has the hiver, a creature that inhabits people, drives them mad, and leaves with impressions of them when they die. A hiver inhabits the protagonist, Tiffany. It is eventually driven out, but for a while Tiffany has trouble figuring out who she is. By the next book it's all been settled, except for the memory of this one wizard who stirs every now and again to translate something or randomly exposit. It's not Sharing a Body or anything like that; he's called "a ghost of a ghost", not self-aware.
 * Also, Jeanie, the Nac Mac Feegle's Kelda, is able to access the memories of all Kelda that have been and will be via a ritual.
 * In E. E. "Doc" Smith's The Skylark of Space, the heroes befriend an alien race that builds mind-reading machines. They use one of these machines to learn each others' languages. Later, they use one on the brain of a dead enemy to learn his secrets, effectively gaining the memories of the dead person.
 * Malazan Book of the Fallen: Apsalar is possessed for a while by Cotillion, the god of assassins, and gains some of his memories along with great skill at knife-fighting.
 * Introduced subtly at first, this becomes a major plot point in Pamela Dean's Secret Country trilogy.
 * Ghostweight, a short sci-fi story by Yoon Ha Lee. A woman plans her Roaring Rampage of Revenge against the mercenary fleet that destroyed her people with the help of one of their 'ghosts' -- it turns out the ghost is not all he appears to be.
 * In Robert Westall's Urn Burial, the Fefethil war-leader Prepoc's tomb included a 'memory-helmet' which gives it's human discoverer, Ralph Edwards, insights into Prepoc's past life by showing him 'snapshots' of things that had happened in it's owners life.

Live Action TV

 * Sharon "Athena" Valerii still had all of the memories of Sharon "Boomer" Valerii up to a certain point in Battlestar Galactica. This goes true for other Cylon models as well, but the Eights are the only model who we have seen sharing memories. Another Eight does it again in 'The Hub'.
 * In the Red Dwarf episode Thanks For The Memory, Lister gives Rimmer 12 months of his memory as a birthday present. He really should have bought him a tie...
 * Dollhouse Actives usually have Fake Memories, but sometimes get the memories of other people. Some of their fake personas are constructed from bits of actual people (anyone scanned by a Rossum medical brainscan), such as "Ellie Penn" in "Ghost".
 * In the Buffyverse, potential Slayers have a subconscious memory of the actions of past Slayers. While this usually only manifests through bizarre, monster-filled dreams, in the case of Dana (in the Angel episode "Damage") the memories combined with her already fragile psyche to send her on a killing spree.
 * Another example comes from the Buffy the Vampire Slayer episode "Halloween"; Xander is magically transformed into a soldier, giving him memories of various military tactics and operational rules that come in useful in "Innocence" and "Graduation Day".
 * In Fringe, this is done to
 * The Trill in Star Trek are small slug like creatures that can bond to a host body, and when the body dies it is implanted in a new one, giving it all the memories and experiences of the previous hosts
 * Also in the The Next Generation episode, "The Inner Light," Captain Picard receives a lifetime of memories belonging to a man named Kamin on a dying world through Alien Phlebotinum.

Video Games

 * Fate/stay night Masters and Servants can see each others' memories while they sleep. This reveals Saber and Archer's backstories, goals, personalities and identities. They also tend to depress both Servants and Masters because the things they see tend to be real downers.
 * In Baroque, the brothers "Left" and "Right" retain each other's memories when each of them die to replace each other. The kicker: For quite a bit of the game, they don't know the other exists. That wacky Amnesia.
 * Bioshock and System Shock 2 have these as a result of each games Applied Phlebotinum. While walking along, your character will occasionally see ghosts acting out what usually turn out to be their last moments alive.
 * To be clear, it's revealed in an audio diary found near the beginning of "Arcadia" that Bioshock!
 * It's implied that from Knights of the Old Republic is experiencing some... feedback from her Force Bond. Probably explains the Sanity Slippage.
 * In Final Fantasy V, Krile inherits the abilities of.

Web Comics

 * In the webcomic Inverloch, Neirran absorbs the mind of another mage who was dying. This gives her all his memories and access to all the spells he knew.
 * In MS Paint Adventures, future Dream Rose "survives" her time line ceasing to exist by fusing with her present dream self, giving her memories of the alternate timeline.
 * El Goonish Shive: Ellen is an Opposite Sex Clone of another character, with all of his memories. Then Nioi showed up. Nioi claimed that since Ellen's soul was barely a couple months old, while her body and mind are as old as she feels she is (about 17), she'll end up going insane. So Nioi "offers" to "fix" the problem. For the next few weeks, when she slept, Ellen dreamt of life in another world, where she was born a girl (not a clone of a guy) and grew up normally. She retained all the memories of this other life, down to her own birth. It's so far caused her as much angst as relief.

Web Original

 * Agent Washington from Red vs. Blue received the memories of the Alpha AI and its creator/template, via its Living Memory component, Epsilon.
 * The A Is in general, particularly Alpha, are examples of this, with their memories being based on their creator's.