Deliberate mistake: The tanks used in the film are German "Leopards", never used by the US army.
Deliberate mistake: During "Izzy"'s inaugural concert with Steel Dragon, there are two shots that are recycled during the first song. One is the rear shot of the guitarist in a low stance rocking back and forth, and the other is Jennifer Aniston raising her arms in the air and screaming for the band. Not only is the repeat a mistake, but when they reuse the shot of the guitarist, the second time it is not in time with the music.
Deliberate mistake: During the final scene, where Dom and Brian are dragging, you clearly hear that the Dom's car is straight piped. When the Charger (Dom's car) is spinning, you see that the car has a complete exhaust system.
Deliberate mistake: In the infamous coin toss scene, Cuba's call is disputed. However, it appears that the coin on the ground is in fact in agreement with his call. However, he explains later that they use a special commemorative coin that is hard to read as it may have what appears to be a head on both sides. Therefore, the coin may have had a head come up, but it was agreed that that side would be 'tails'.
Deliberate mistake: The energy the meteor would displace upon impact would have created a crater of significant size compared to what was portrayed. It also didn't appear to have any impact to the structure of the cavern it crashed into either.
Deliberate mistake: Just after arriving in the 21st century, Thibault and André enter an elevator and scare away its occupants. Attempting to chase them, the elevator doors close despite their attempts to keep it open. Elevators have a safety mechanism which opens the door when they encounter resistance. This was ignored deliberately in the film for comic effect.
Deliberate mistake: Frequently during the movie, British surgeons are referred to as "Doctor". In Britain, surgeons are always referred to as "Mister"; this is a hold-over from the surgeon's non-medical past (barbers, etc). This would likely be confusing to American audiences.
Deliberate mistake: Jay and Silent Bob are kicked off the bus to Hollywood because they don't know they have to buy a ticket. However, in 'Chasing Amy,' Jay tells Holden that he and Silent Bob are taking a bus to Chicago. Jay even has what appears to be bus tickets in his front pocket, so he knows a ticket is needed for an interstate bus. And even if he thought it was free then, he would have found out about needing a ticket much earlier. Obviously, the earlier scene was disregarded for the sake of the joke.
Deliberate mistake: In Silence of the Lambs Starling was right-handed. In Hannibal she is left handed because we see her writing with her left. Julianne Moore, the new actress who plays Starling is left handed whereas Jodie Foster was obviously right-handed.
Deliberate mistake: In the scene where Gordon is in the shower wearing his dad's scuba gear and his dad throws the soap on a rope into the toilet, Gordon dives into the toilet to retrieve it. During the camera shots from beside the toilet, you can see that the back of the toilet has been removed so as not to block the view of Gordon with his head in the bowl, but in the other shots, you can see the back of the toilet just fine. (00:34:00)
Deliberate mistake: When the captain jumps towards Scott, the distance between the two rows of seats is three times bigger than the other rows shown, obviously to allow for the fight, but still really weird when you look at it.