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: 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: 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: 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: 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".
Trivia: During the audio commentary, Jake Gyllenhaal actually spots some continuity mistakes, and points them out. The director then proceeds by telling him he's not doing the film any justice.
Trivia: When Freddy and Daryl are driving in the car listening to the Spanish hip hop music, at the back window there is a bee persistently trying to get into the car.
Trivia: The woman who accidentally calls Burt Gummer (Michael Gross) "Mr. Goober" is actually played by Michael Gross' sister Mary. Like her brother, she's an actress who was a co-star on Saturday Night Live for several years in the 80's, and has done a smattering of film, television and voice-acting roles since.
Trivia: The actor Alec Wilson, who plays Jacko in Crocodile Dundee in Los Angeles, also played a goon in the second Crocodile Dundee movie. Just like in the second movie, where he gets freaked out when the Aboriginal tracker disappears, his character also gets freaked out in this movie too when Mick Dundee does it too.
Trivia: Pat Crawford Brown is just four years older than Joan Collins, despite them playing mother and daughter.
Trivia: When Michael collides with a cello player at the charity fundraiser towards the end of the film, the cello player lets out a Wilhelm scream.