Deliberate mistake: Bender goes back in time to two minutes before Fry came back to the past. But if you time it, it was actually only 1 minute and 42 seconds.
Futurama: Bender's Big Score (2007)
1 deliberate mistake
Directed by: Dwayne Carey-Hill
Starring: John DiMaggio, Katey Sagal, Tress MacNeille, Billy West
Other mistake: When Leela is signing the petition, Amy grows a third arm for a split second.
Al Gore: Finally, I get to save the Earth with deadly lasers instead of deadly slide shows!