Mistakes in the IMDb top 250
Continuity mistake: When Sonny is shot at the toll booth the front windshield is torn apart by bullets yet when the bodyguards arrive thirty seconds later, the windshield is intact.
Other mistake: When young Vito Corleone shoots Fanucci in the chest at the doorway to his apartment, in a continuous shot, a wound/blood bursts from Fanucci's white vest. When Fanucci proceeds to tear his vest open seemingly in disbelief he has been shot, there is no entry-wound, blood or hole in his white shirt directly under where the wound appeared in his vest.
Continuity mistake: During the interrogation scene, when Batman beats up Joker, Joker's hands are holding Batman's forearms upside down (from underneath). When the frame changes his hands are now on top of Batman's forearms, then it cuts back and his hands are under again.
5: Pulp Fiction
Continuity mistake: When they are giving Mia Wallace the adrenaline shot, they mark her chest with a red magic marker. When the shot has been given, the red mark has disappeared.
Continuity mistake: When Blondie abandons Tuco in the desert, watch the rope around Tuco's neck. It changes between shots, sometimes over his left shoulder, and sometimes hanging down in front of him. It is not due to the camera angle.
Factual error: When the camera took a shot on a train coming to a station in Czechoslovakia, you can see electric cables above the train tracks. There was no such thing in Czechoslovakia as electrified trains in the 1940's. The electrification started in the 1950's.
8: 12 Angry Men
Deliberate mistake: When Henry Fonda decides to recreate the old witness's ability to get to the door in 15 seconds, he asks another juror to time his walk. The scene never cuts away, yet the juror who times it says it took 41 seconds when in reality it takes closer to 30.
10: Fight Club
Continuity mistake: Close to the end when Edward Norton runs up to the front of the empty building and Brad Pitt appears, he tries to break the glass door by pushing a bench into the door, but it doesn't work. He doesn't move the bench and he then shoots at the glass and breaks it. When it shows him walking through the broken door, the bench has disappeared.