Deliberate mistake: When Will is bound and brought before "Chief" Jack, Will says, "The compass!" and there is a close-up of the compass, as it hangs to the right of the long striped cloth. However, in all other shots the compass hangs to the left of the red and white striped cloth. This is a flipped shot - note the large buckles. (00:24:00)
Deliberate mistake: Bare shoulders are forbidden in the Vatican premises, so the sexy dresses in the party would not be allowed.
Deliberate mistake: When Lex tests the crystal fragment, it knocks out all the power on the airplane Lois is flying in, yet the flight attendant's amplified voice can still be heard over the speakers. (00:30:40)
Deliberate mistake: In many of the non-CG generated snake shots, what appears to be a very venomous coral snake is in fact either a scarlet king snake or a California mountain king snake (depending on the shot). These are much safer, non-venomous alternatives for filming with the actors. Look for the ordering of the colored bands (red/black=venom lack, red/yellow=kill a fellow).
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: On the roof of the sunken building, Bond tries CPR on Vesper, then quits when he realizes that she is dead and sits away from her body. Watch her right leg carefully when he returns to her body and cradles her in his arms - she flexes it upwards at the knee. Yes, I know that electrical impulses in a dead body can cause muscle movements, but this was obviously the actress involuntarily bracing herself from slipping on the slanted surface. Cut to Mr. White walking away with the money and when the camera returns to the roof, Vesper's leg is lying flat again. (02:18:00)
Deliberate mistake: When Hellboy is attacked by the spider-lady, as the spiders begin to descend on him to steal the sword, you can easily tell that some of the shots of the spiders coming down are repeated 2 or even 3 times, and simply flopped horizontally to appear different.
Deliberate mistake: After Doug finds where Minuti was killed and set on fire, he walks over to a dock where he sees Minuti's arm being eaten by alligators. Minuti had been dumped in the water 4 days prior, yet his hand is perfectly intact with no signs of burning, bite marks or weather/water damage of any kind.
Deliberate mistake: The first time the warriors ride out during the full moon, the shot of the moon shows that it is in the phase of "half moon".
Deliberate mistake: During the scene on the train in lounge car, a picture on the wall prominently shows an ALCO PA locomotive. The movie was set in 1945, but this locomotive was first produced in 1947.
Deliberate mistake: When Selene and Michael are driving a truck, chased by Marcus, at one point in the chase Marcus flies directly ahead of the truck and stays upright in the air with wings outstretched, facing the truck. Given that the truck is travelling at high speed and Marcus is using wings for flying, it is just not possible. It can't be attributed to Marcus' inertia - he stays in front of the truck for a couple of seconds, long enough to lose any speed advantage he had before.
Deliberate mistake: When the armored car hit's the police car the police car flies up in an explosion. Due to the size, style, and weight of the armored car, the police car should've been run over and crushed. (01:02:05)
Deliberate mistake: Throughout the movie, Seagal's voice changes. In some scenes, his lines are spoken by someone else (with a much coarser voice) and dubbed in, which is confirmed by numerous sources over the internet.
Deliberate mistake: Some of the same crash scene footage is used before and after the Applebee's commercial break.