At the Options screen, hold L1 + R1 and enter the following:
Invincibility:
Triangle, X, Triangle, X
Faster cars:
Square, Square, Square, Square
Much faster cars:
Triangle, Triangle, Triangle, Triangle
Instant explosion:
Triangle, Triangle, Square, Square
Super jumps:
Square, Square, Square, Triangle. Use the horn to jump.
Alternate view:
Circle, Circle, Circle, X
Show speedometer:
Triangle, Triangle, Circle, Square.
Grid view:
Circle, X, Circle, Triangle
Freakout view:
Triangle, Circle, Triangle, Circle
Itchy and Scratchy Cartoon:
Collect every card in the game and go to Lisa'a level. In the Android's Dungeon, talk to the Comic Book Guy and buy a ticket for the cartoon. Then, go watch the cartoon at the Aztec Theater.
New Year's Theme:
Set the system date to January 1st.
Halloween Theme:
Set the system date to October 31st.
Christmas Theme:
Set the system date to December 25.
