Continuity mistake: In the scene on the Golden Gate Bridge when the apes are pushing the bus, the police shoot the bus numerous times, but when the camera goes off the bus and then shows the bus again (twice) the bullet holes are not there anymore.
Continuity mistake: When McClane is driving the police down the ramp to the tunnel so he can elude the helicopter, the car's windshield doesn't have any bullet holes or cracks in it, even though it did just a few seconds earlier. (00:37:55)
Continuity mistake: Near the end of the film, when Drs. Malcom and Harding are looking for the baby T. Rex in San Diego they arrive at the new InGen Jurassic Park. The car brakes hard, skids a little pulling a trailing cable for a portable light. The lamp falls. When they get back into the car with the baby T. Rex, to use it to entice the adult back to the ship, the lamp is standing again. (01:46:52)
Continuity mistake: During the scene when Thomas Crown is sailing, you can see the weather change from very dark and stormy, to just cloudy, to blue sky and sun, depending on the shot. (00:36:30)
Continuity mistake: When Bryan chases the spotter, all of the cars that had to stop are all positioned at different angles. After the spotter dies and Bryan walks back along the bridge, one of the shots shows all of the cars now parked in a perfectly straight line.
Continuity mistake: In the scene early in the movie where Kirk is talking to Sarek the guns on the wall are suddenly rearranged. (00:23:50 - 00:24:45)
Continuity mistake: In the cafeteria scene, Ripley gets a square of what looks like cake and pours half a glass of orange juice. When she sits down her glass is full. (00:27:00 - 00:27:50)
Revealing mistake: When Father Karras sprinkles holy water on Regan, they forgot to paint her ear lobes and it looks terrible. (01:32:30)
Continuity mistake: When Samuel looks at the handgun in the drawer, the gun is vertical in closeup, but the grip is tilted left when Samuel reaches for it. (00:46:20)
Visible crew/equipment: When Bill's fiance is driving over after the first tornado, when the truck lands, she swerves and she stops. As she is getting out, a camera is visible. When the camera backs up though, a crew-member pulling it back is visible in the door.
Continuity mistake: Towards the end, when Bruce Willis notices the writing on the aspirin bottle, he leaves it in the phone booth and the camera jumps towards it a couple of times. In the first shot the writing's almost vertical, but in the following shots it's at a definite angle. (01:48:35)
Continuity mistake: When Gene Hackman is helping his wife zip up her dress her hair goes from hanging straight down her back, to being over her shoulder. It cuts without giving enough time to assume that she moved her hair.
Continuity mistake: When Mrs. Waterhouse walks into the livingroom and greets her three babies, there is a large area rug in front of the coffee table. However, as the babies fly towards her in the wide shot facing her, that area rug is gone! (00:22:55 - 00:23:50)
Continuity mistake: When Doug is running from the bad guys after finding out what was going on from his "wife", he tucks his big gun in to his jacket pocket. When he is running through the scanner, that big gun is now in his pants. (00:28:15)
Factual error: Take a look at Google Earth - the section of the Golden Gate Bridge Magneto breaks off (about a mile - tower to tower plus a section each end) isn't anywhere near long enough to reach Alcatraz from anywhere on the mainland.
Revealing mistake: When Jackie rescues the kid from the burning petrol truck you can see that they used a dummy when he dropped the kid. (01:11:36)
Visible crew/equipment: During the freeway chase, when both the Hummer and the Dodge Magnum are shown flipping over at the same time, the "Bay Buster" camera truck is briefly visible in the background.
Continuity mistake: In the scene in the library, when Evie is putting back the books. She leans over to put the book back, but it falls to the ground and she is balancing on the ladder. When the camera cuts back to show the whole ladder, the book is nowhere to be found on the floor. (00:13:00)
Visible crew/equipment: As the camera moves in on the bull that is about to be grabbed by the vampire, if you look under the bull, you can see two men hiding behind it. You can see their legs. They are probably there to keep the bull standing still. When it cuts they are gone. (00:26:05)
Factual error: When Arnold is in the police station reporting that he has a clone and passes through a control room, one computer screen is flashing "OVERIDE." The correct spelling is "OVERRIDE." (00:38:05)