Passwords from main menu:

WHATYOUGET: 1-shot kills

MONKEY: Get gold on level

BOING: Bouncing grenade

LONGSHOT: Snipe with any weapon

BULETZAP: Immunity to bullet damage

HABRDASHR: Men with weird hats

Enter during gameplay:

start, square, L1, circle, R1, triangle, L2, select, R2: Invincibility

circle, L2, square, L1, select, R2, triangle, select: Unlimited ammo