Pirates of the Caribbean: Jack Sparrow makes the suggestion once that Will Turner may be a eunuch due to the fact he hasn't got a girlfriend (again Jack's speculation). Will is thus repeatedly referred to as a eunuch (mostly by Jack himself).
While it could be argued that "sea turtles" became more of an in-movie meme, the fact that it was Jack who seemed to have begun it seems to indicate its mention by other characters is more or less just their way to poke at Jack.
The little pirate of Jack's crew has on multiple occasions proven himself to be capable and talented. But he'll always be the dwarf in At World's End who got blown back into the very hole he had just worked his way out of... by the recoil of a large gun he was toting. Later on in the film, he uses the same gun without the comical effect.
Barbossa is an unmovable monster who led his crew to reclaim every last piece of stolen gold they'd "frittered away" and undo the curse set upon them. He performed the marriage ceremony between Will and Elizabeth. He also rocks a fancy wooden leg in On Stranger Tides. But he's still 'that guy who eats apples.'
Also: "What ARRRR ya doin'?"
Johnny Depp in general is now typically only known for his more off-the-wall performances (i.e. Edward Scissorhands, Willy Wonka, Jack Sparrow, Barnabas Collins, and Tarrant Hightopp). Hardly anyone seems to remember that he played a Vietnam War soldier alongside Charlie Sheen in Platoon.
The casual manner in which Darth Vader dispatches his incompetent underlings, as well as taking into account The Law of Conservation of Detail, suggests that this is a common occurrence.
There's also how the other officers/troopers react to it. They look uncomfortable, but not really shocked or surprised. Their reactions suggest that this is indeed a common occurrence.
Another thing he won't live down is the Wangst he spouted in Revenge of the Sith. While he wasn't exactly optimistic in Attack of the Clones, he kept having horrible visions that his wife will die and was desperate to save her.
Leia kissed Luke precisely twice, once for luck and once specifically to make a point to Han. There is nothing particularly sexual between them, but some people seem to genuinely believe they were screwing like incestuous bunnies before Return of the Jedi. Wishful thinking? Squick!
The other thing that people conveniently forget is that neither Luke nor Leia learned they were brother and sister until Return of the Jedi. And neither did the writers.
A more unfortunate Star Wars example: it seems no one can mention General Grievous without someone bringing up his... lessthan dignifiedending.
Boba Fett will never live down looking cool, despite all his attempts to prove that he is whiny and untalented. Not to mention Han dispatching him with a stick, while blind.
Lando is perpetually known for betraying Han and the others in Cloud City despite the fact that he did so to protect the city from the Empire, orchestrated their escape from the city, hid in Jabba's palace undercover to rescue a frozen Han, and piloted the Millenium Falcon into the reconstructed Death Star at the Battle of Endor. Lampshaded on an episode of Robot Chicken.
Various sources claim that Billy Dee Williams really will defend Lando's actions at length, in the very same way that he does in the Robot Chicken sketch.
Lando has never lived down the incident with the Millenium Falcon's hyperdrive, either, simply because he was under the impression that his mechanics would fix it rather than the Imperials sabotaging it further. While he did truthfully claim "It's not my fault!" (same as Han did), in later Expanded Universe works ships he attempted to fly never worked as intended, with him once again spouting his new catchphrase.
Spaced referenced this as well with the phrase "You Lando!" being Tim's euphemism for traitor.
In-universe, Heir to the Empire suggests that Lando losing the radar dish atop the Falcon while flying it through the Death Star II is one of these, though at least with some justification:
Han: At least the sensor dish is still there. Lando: You're never going to let that go, are you? Han: You said, "not a scratch".
Don't forget about Admiral Ackbar who can detect TRAPS!
Made worse by the fact that people tend to forget that Lando was the one who figured out it was a trap and Ackbar just labeled it so.
The child actor that played Anakin Skywalker in The Phantom Menace will never live down his role in the film; the kid got constant ridicule from fanboys who hated the film, belittled by critics for his not so impressive acting skills, and was constantly bullied at school by other children for his involvement with the movie. The downward spiral caused the actor to destroy all Star Wars memorabilia he owned, refuses to talk about the Star Wars franchise while hating it, and grew up to be very bitter and cynical while quitting the acting business.
Complicating matters, several Bond films (such as Thunderball, Goldeneye and Die Another Day) have genuinely evil beautiful henchwomen as well as heroines, and Bond will sleep with said evil henchwoman, in almost every single film. Doesn't help that Bond is also a frequent offender of tropes like Sex Equals Love and "Not If They Enjoyed It" Rationalization.
Clerks II both plays it straight and subverts it with Dante and Randall's former classmate Lance "Pickle Fucker" Dowds, who had earned the nickname in an incident of high school hazing. After Randall recounts the incident where Lance earned the nickname, Lance replies that nobody but the aimless Randall Graves would remember the incident at all. Cue Jay walking in and saying "Hurry up Pickle Fucker, I wanna get my cow tipper on!" As Jay is leaving, he yells off-screen, "Hey, Silent Bob, some pickle fucker just gave us free eats!" after Lance does so, revealing that Jay occasionally just randomly calls people "pickle fucker".
The parodydisaster movieThe Big Bus contains the immortal line "Jeeze! You eat one foot and they call you a cannibal!"
Invoked in David Cronenberg's The Brood when Robert Silverman's character intends to sue the psychiatric clinic (run by Oliver Reed) that he believes to be responsible for his lymph cancer. He knows he's going to lose the case, but he also knows that in a few years, people won't even remember the verdict.
All they'll remember is the slogan: "Psychoplasmics Gives You Cancer." Catchy, huh?
In For Your Consideration, Harry Shearer's character, Victor Allen Miller, a dramatic actor who has been a veteran of stage for 40 years, yet all most people seem to remember of him is being a hotdog pitchman on TV when he was younger.
Joel Schumacher is seen by many as the director that killed the 90s Batman franchise with Batman & Robin. A prolific director with interesting films under his belt, yet for the fan(boy)dom he's branded as the director of Batman & Robin.
The Other Guys: Mark Wahlberg's character, Terry Hoitz, became a pariah within the NYPD and the city as a whole when he shot a man in a Yankee Stadium corridor during the World Series, not knowing it was Derek Jeter. Although he's been on desk duty ever since then, his coworkers STILL don't let him forget.
Look at all the Labyrinth fanfics that include Jareth saying "precious" or "precious thing". He only said that phrase ONCE in the whole movie.
Also, David Bowie's rather tight pants that draw the eye no matter how much you try to resist.
Joe Dirt: After being abducted by "Buffalo Bob", everyone asks Joe if he was harmed in certain ways, even though nothing terrible really happened.
The Gangster Squad trailer showed a scene of the antagonists shooting people through a movie theater screen. This trailer was shown right before James Holmes started his shooting rampage in Aurora, Colorado. The movie failed at the box office likely because of it
Thanks to the Hitler Rants parodies, a number of Downfall characters are best known for something inconsequential they did.
Most of the comedians from the first half of the 20th century like Charlie Chaplin, Buster Keaton, Laurel and Hardy, the Marx Brothers, The Three Stooges are often dismissed for being nothing else besides people throwing pies into each other's faces. Despite the fact that most of these comedians, like Keaton and The Marx Brothers, never made a film featuring pie fights. And even with the other comedians the amount of films with pie fights can be counted on one hand.