Trivia: Matthew Perry bet Bruce Willis that if the film would open at the top of the charts in the US (which it did) he would have to guest in an episode of Friends for free (which he did, plus all further episodes payments were given to charity).
Trivia: At the end of the scene in which Sophie coerces Oz into going to Chicago to rat out Jimmy to the Gogolaks, Oz makes a strange motion in which he waves his hands and makes odd noises. This characteristic anomaly was consistently used by Matthew Perry on the TV show Friends after something happened that he'd rather forget.
Trivia: In the car, Willis asks Matthew Perry if 'He's always this nervous?', to which Perry replies, hastily, 'Yes'. This is the exact same exchange that Perry has with Neve Campbell in Three To Tango.