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: When Clarice tries to push up the blocked door of the self storage container she puts her gloves on her lap. In the next scene the gloves have disappeared. (00:24:15)
Continuity mistake: When Vernita and The Bride are talking in the kitchen and Vernita shoots The Bride from the cereal box, you can see the bullet hole in the back wall of the kitchen, but then a little later that part of the wall doesn't have any bullet holes. Also, not only is the bullet hole not where you see it hit in the first place, it's on the other side of the bride's head, along with the splatter from the cereal box.
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: Bret shoots himself under the chin and a hole is blown in his forehead. Moments later when he's on the ground, for a split second, you can see his forehead completely unblemished. (01:03:00)
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: When Helen and Jacob walk out from under the bridge, at the very end of the movie, we see footsteps being made in the metal "sand". When the camera pans to a shot from behind, the footsteps made in the sand are gone.
Continuity mistake: During the prison fight scene, Silk Spectre's stiletto boot heels are alternatively flat-soled from shot to shot, for the stunt woman's benefit.
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 housewife Alice is trying to escape with her daughter in the laundry room, she slams a mop through the ceiling. When she slams the mophead through the ceiling the last time and pulls it out, the hole left behind is maybe one foot across. When she lifts her daughter up into the hole it is now a good two or three feet across and reaches from ceiling support beam to support beam. (00:09:20)
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: 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)
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 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)
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)
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)