The Simpsons Game Cheats

Unlimited Powers for all characters:
At the Extras menu, press Triangle, Left, Right, Triangle, Square, L.
(supplied by: toni_barbie_yellow)

Unlock All Movies:
At the Extras menu, press Square, Left, Ssquare, Right, Triangle, R.
(supplied by: toni_barbie_yellow)

Unlock All Cliches:
At the Extras menu, press Left, Square, Right, Triangle, Right, L.
(supplied by: toni_barbie_yellow)