Deliberate mistake: When Kate Barlow shoots the Sheriff, she shoots him between the eyes, but when she kisses him there is no hole or anything on his face.
Deliberate mistake: When Leonard snaps a picture of Jimmy's body his head is lying between his shoulders looking straight up, but in the polaroid his head is lying to the right, and it is, in fact, a different actor altogether. (01:39:10)
Deliberate mistake: At the end of the film when Pacino and the gangsters are shooting each other on the escalator, the escalator takes a long time to get to the bottom, way too long.
Deliberate mistake: When Tom Hanks is picked up at the airport by a taxi, its license plate number is TX7943. Later when he is picked up at the Ramada Inn, he is picked up by a taxi with a different driver, different numbers on the top, but has the same license plate number.
Deliberate mistake: When Arthur follows Guinevere to the meeting with Merlin, her and the trees' shadows point at the viewer. Only Arthur has two shadows, one points to the left. The source of the moonlight is below the next ridge, and it's bright like a floodlight. Later, when Arthur is talking to Merlin, his face is always illuminated, even after a 180°-turn. (00:59:00)
Deliberate mistake: This has the old T.V. show style "it was 6 a.m. on January 7th we ... " beginnings to the scenes. Pay attention to those times and dates. They're not even close to being in sequence. I mean days, not just times.
Deliberate mistake: With John Cusack leaning to the side to pull Diane Lane and the dog from the water, the rowing scull should have nearly tipped over, yet it leans only slightly. Later in the same scene, the normal instability of such boats can be seen when tipping occurs to a greater degree simply from the dog moving.
Deliberate mistake: When Raza is chasing the "empty" train, as it goes over the trestle just before he stops it, you can see the engineer in the train's engine.
Deliberate mistake: Near the end of the movie, there is a shot of the "Iwo Jima" with the two recovery helicopters taking off. For a moment, you can see the number 11 on the inboard side of the ship's island, which identifies it as the USS New Orleans (LPH-11), a sister of the Iwo Jima. Admittedly, it was the best the producers could do, since by the time the movie was made, the Iwo Jima (LPH-2) had been decommissioned.
Deliberate mistake: Whenever we see the computer generated Lou, he never has genitals.
Deliberate mistake: Old Weird Harold's pants fall down twice in the film. His boxers are different colors each time; once they're red, the other time they're blue. The director admits to this deliberate mistake in the commentary, siting his interest in seeing if people will notice.
Deliberate mistake: In the funeral scene of Wallace's father and brother, the little girl picks a flower for young Wallace. Look closely when she picks the flower- its already been cut. [This was to make it easier for the little girl to pick it so not to hurt herself on the thorns.]. (00:11:20)
Deliberate mistake: When Zoom is moving the documents from the desk to the floor for Marsha to pick up, she quite blatantly catches him two or three times, but continues on with her business.
Deliberate mistake: Due to the thin tissue and blood supply to the lips, after Carly ripped the superglue from her lips she should have bled profusely, requiring steady pressure for a minimum of five minutes. However, that would have obviously slowed the tension of the movie too much.
Deliberate mistake: When Layla is having babies and the first one comes out there is already a nappy on the baby. (00:06:45)
Deliberate mistake: In a couple of scenes, Bandit's Trans Am's engine sounds are dubbed, and you can hear the shifting of a manual transmission when his car was an automatic.
Deliberate mistake: When Denzel Washington is in the bathroom, he discovers the camera monitoring him from the air vent, by seeing the light on the front of the camera. Any spy with common sense would not install a hidden camera with a light on it.
Deliberate mistake: Elizabeth Shue uses a drawer handle as an electromagnet. OK if it's really a magnetic material but lab furniture is generally made of aluminium or stainless steel which is not. There is no way that they would use an iron handle in a potentially wet, and hence corrosive, environment such as a freezer.
Deliberate mistake: You might be wondering where Terry suddenly comes up with Jolly Jack all of the sudden after escaping the lab. In the commentary, they say that the Joker, in his transmission to Terry in the lab, was supposed to be eating out of a candy jar with "Jolly Jack" on it, but couldn't have it due to time constraints.
Deliberate mistake: In the championship game, when number three on the other team hits a home run, he never touches home plate. Home plate is where all of the players are crowded around (primarily the ones to the left of the scene). The player makes a "jump stop" at the batter's box. The Bears could have waited 'til the player went back to the dugout; the catcher, with the new ball in play, would have stepped on home plate, and the home run never would have counted.