Enter at start screen before main menu.

• Infinite Ammo: R2, R1, TRIANGLE, L2, L1, UP, R2, R1, TRIANGLE, L2, L1, UP
• Add Weapon: UP, DOWN, LEFT, RIGHT, CIRCLE, SQUARE, UP, DOWN, LEFT, RIGHT, CIRCLE, SQUARE
• Psychedelic Mode: UP, R2, CIRCLE, LEFT, TRIANGLE, SQUARE, L2, L1, CIRCLE, R1
• Infinite Health: R3, L3, RIGHT, LEFT, L1, R1, R3, L3, RIGHT, LEFT, L1, R1
• Unlock Missions and Pictures: L2, R2, L1, R1, L1, L2, L2, R2, L1, R1, R1, R2

Enter Cowboy as your name when you start the game and when you enter special forces you will be wearing a cowboy hat in certain cut-scenes and movies.