Trivia: The combination lock of the safe in Israel doesn't read some numbers, it reads four letters, being J, W, H, and some other you don't see. The order of them, shown when Quinten opens it, is JHWH, this being the ancient name of Christ in Hebrew.
Trivia: Part of the movie was shot in Toronto (actually, the guys' apartment is in Toronto, I remember seeing interviews), along with where it takes place, Chicago. If you watch the credits and you watch where the cast is dancing while Al Green's singing, you can see a Tim Horton's Roll Up the Rim billboard in the background. Also, that scene takes place at the Eaton's Centre in Toronto.
Trivia: Whenever Nicholas Cage had to fall over, he had to be lowered down on a harness onto a crash mat because he hates falling over.
Trivia: Eric Stoltz was nearly cast for the role of "Rusty Nail", but director John Dahl felt Stoltz didn't sound scary and intense enough so the part was given to Dahl's first choice, Ted Levine.
Trivia: The kid who is very good at stocks and wants to work on Wall Street name is Dobbs. Dobbs is a company on Wall Street.
Trivia: If you buy the movie on DVD you get a postcard with Mary-Kate's and Ashley's photo on it along with their signatures. The signature of Ashley is on Mary-Kate and vice-versa.
Trivia: The hand that lights the lighter in the cooking scene is the director, Gregor Jordans' hand. It says this in the DVD's audio commentary.
Trivia: The nurse who brings Bev her baby in the hospital is played by Tracy Reiner, director Penny Marshall's daughter.
Trivia: The way the god of sleep's goat legs were achieved usually consisted of hiding the actor's legs behind or below whatever the character was sitting on. However, when he had to walk, the actor wore a pair of green screen pants with the goat legs going down to his knee. There was padding from the bottom of his knee to the top of his foot so he wouldn't make any sound he wasn't supposed to. Look behind him when he walks in a crowd and you'll see that nobody gets less than two feet behind him. This is most noticable in the slumber party scene and when monkeybone steals Stu's exit pass. To see what I mean, look at the special features and watch "The Secrets of Monkeybone"
Trivia: The character of Ira Chuvney is a composite of Jewish comedian Mel Brooks, who was also a writer for Sid Caesar.
Trivia: The manager of the Formula One team Williams (Frank Williams) moves around in a wheelchair, just like the manager in Driven. This is caused by a car accident.
Trivia: This is Charlize Theron's second movie with Keanu Reeves. She starred with him in Devil's Advocate as his wife and in Sweet November they are lovers.
Trivia: Most of the conversations between Robert De Niro and Marlon Brando are improvised.
Trivia: In the scene where Archie is introduced to the forest animals, a man presses the button to turn on the song. This man is Doug Seus, the famous bear trainer whose bears have been in at least 8 other movies.
Trivia: During the scene where Billy Connelly is talking to the Russian family the mother says something about the insurance companies which the father translates as "they are not nice people". The word the mother uses is "svoloch" which would more accurately be translated as "they are f**kers."
Trivia: At the beginning of the film when Colin Hanks' character is trying to set Ben Foster's character up with the unlucky/clumsy blond, he mentions the school name as Rosnell High, which is a thinly-veiled reference to his school in the TV series Roswell High.
Trivia: Shortly after completing this film, Vince Vaughn was involved in a bar fight in which his co-star Steve Buscemi was stabbed in the throat, head, and arm trying to back him up. Ironically, it was Vaughn's character who stabbed Buscemi's character in the film.
Trivia: Near the end of the movie, a teacher yells, "Hey teacher, leave those kids alone." A clear reference to Pink Floyd's song "Brick in the Wall".