the simpsons hit and run[center]Cheat: Different Camera
At the main menu (the livingroom), go to the options screen. Hold down L1+R1, then press CIRCLE, CIRCLE, CIRCLE, X to activate the cheat. A horn will confirm entry.
Cheat: Pressing Horn Button Jumps
At the main menu (the livingroom), go to the options screen. Hold down L1+R1, then press SQUARE, SQUARE, SQUARE, TRIANGLE to activate the cheat. A horn will confirm entry.
Cheat: One-Hit Wrecks
At the main menu (the livingroom), go to the options screen. Hold down L1+R1, then press TRIANGLE, TRIANGLE, SQUARE, SQUARE to activate the cheat. A horn will confirm entry.
Cheat: Much Faster Cars
At the main menu (the livingroom), go to the options screen. Hold down L1+R1, then press TRIANGLE, TRIANGLE, TRIANGLE, TRIANGLE to activate the cheat. A horn will confirm entry.
Unlockable: Red Brick Car
At the main menu (the livingroom), go to the options screen. Hold down L1+R1, then press CIRCLE, CIRCLE, TRIANGLE, SQUARE to activate the cheat. A horn will confirm entry.
Cheat: Grid View
At the main menu (the livingroom), go to the options screen. Hold down L1+R1, then press CIRCLE, X, CIRCLE, TRIANGLE to activate the cheat. A horn will confirm entry.
Cheat: Trippy View
At the main menu (the livingroom), go to the options screen. Hold down L1+R1, then press TRIANGLE, CIRCLE, TRIANGLE, CIRCLE to activate the cheat. A horn will confirm entry.
gamer_xaf
Unlockable: Itchy and Scratchy Cartoon
Collect all the cards in every level of the game to unlock an episode of Itchy & Scratchy made exclusivly for the game.
miknut1
Easter Egg: Holiday Look
Change your system's internal clock (or play on a holiday) to the dates for Thanksgiving, Halloween and Christmas to experience a different game look.
hiei and yusuke rule
Cheat: Night Mode
At the option menu (at the living room) press X, X, X, X. A horn will sound if you did it right.
Dan P.
Cheat: Drunk Mode
On the main menu (the Simpson's living room), go to the options screen and hold L1 + R1. Enter TRIANGLE, CIRCLE, TRIANGLE, CIRCLE for the cheat.
Brad Paul
Cheat: Invincible Car
At the options screen on the living room, hold R1+L1, and then press TRIANGLE, X, TRIANGLE, X.
gamer_xaf
Unlockable: Multi-Player Racing Game
Collect all the cards in just one level to unlock the multi-player racing mini game.
Cheat: See Credits
At the main menu (the livingroom), go to the options screen. Hold down L1+R1, then press X, SQUARE, SQUARE, TRIANGLE to activate the cheat. A horn will confirm entry.
Cheat: Show Speedometer
At the main menu (the livingroom), go to the options screen. Hold down L1+R1, then press TRIANGLE, TRIANGLE, CIRCLE, SQUARE to activate the cheat. A horn will confirm entry.
Cheat: All Bonus Cars
At the main menu (the livingroom), go to the options screen. Hold down L1+R1, then press X, CIRCLE, X, CIRCLE to activate the cheat. A horn will confirm entry. Note: The game must be 100% complete before this will work. You can select the cars from the phone booth. After inputting the code you'll have to go to a phone booth and press R1 when the selection screen comes up.
Addition by cheezy
Cheat: Faster Cars
At the main menu (the livingroom), go to the options screen. Hold down L1+R1, then press SQUARE, SQUARE, SQUARE, SQUARE to activate the cheat. A horn will confirm entry