The Dark Knight Rises
Spellcheck is necessary for almost every industry—especially entertainment. In one scene from The Dark Knight Rises, "heist" is spelled incorrectly in a newspaper headline. You'd think there was enough money in the budget for an editor...
Star Wars: Episode IV
At first, only real fans of the series noticed this slip-up, but it soon became a popular GIF. One of the Stormtroopers, known only as "Unidentified Head-Bumping Stormtrooper," bangs his noggin on the doorframe while entering the scene. The 2004 DVD re-release of the original trilogy enhanced the incident with an obvious sound effect to draw more attention to the gaffe.