Steve Young, who played professional football for the San Francisco 49ers (among other teams), plays "Bro. Niner." During his scene in the film, Bro. Niner quotes Brigham Young; Steve Young is a direct descendant of Brigham Young.
Sam (played by 'Jeremy Elliot (I)') can be seen reading the book 'Charly'. Elliot starred as the male lead Sam Roberts, in the movie version of said book.
According to the DVD commentary, the scene where Zak gets arrested was shot on 9/11. There is a noticeable look of sadness on the actors faces during this scene that they said was difficult to act through.
Wally Joyner, who played professional baseball for the California/Anaheim Angels (among other teams), plays "Bro. Angel."