Ape Escape
Invincibility:
Pause gameplay and press UP(x6), Triangle(x2), Circle, X(x3), Square, DOWN, UP, RIGHT, LEFT.
99 Explosive Bullets:
Pause gameplay and press R2, DOWN, L2, UP, RIGHT, DOWN, RIGHT, LEFT.
Debug Mode:
Pause gameplay, hold L1 and press DOWN(x2), Triangle.
Play as a Monkey:
During gameplay, press Triangle(x2), Circle(x5).