Cheat: Play as Nicole:
From the title screen, hold L1 + R2 and enter LEFT, UP, DOWN, UP, CIRCLE, UP, UP

Bottomless Canteen Code:
Hold L1 and R1, and then press LEFT, SQUARE, CIRCLE, DOWN, SQUARE, X, SQUARE, CIRCLE.

Unlockable: Hyper Punch Mode:
On the title screen, hold L1 + R1 and press LEFT, RIGHT, CIRCLE, UP, CIRCLE, RIGHT, LEFT

Unlockable: Original Pitfall:
On the title screen, hold L1 + R1 and enter CIRCLE, CIRCLE, LEFT, RIGHT, CIRCLE, SQUARE, X, UP, CIRCLE