Ape mode
Press start to pause game play, then hold Z and press B, B, A, Y, B.
Fez and rollerskates
Press start to pause game play, then hold Z and press X, A, A, A, B.
Reversed gravity
Press start to pause game play, then hold Z and press Y, Y, B, A, A.
Unlimited bananas
Press start to pause game play, then hold Z and press A, X, X, Y, A.
Ape mode...