Infinite Money:
At the title screen, press L1 + L2 + R1 + R2, then press Square +
Triangle + Start. The map selection screen will be displayed. Now hold
L1 + L2 + R1 + R2 and press Circle. If you entered the code correctly,
you will hear a sound. Pause the game and press Left, Right, Up, or
Down to gain more money.
Cheat codes from Bill's Cheat Pages http://www.angelfire.com/ca2/billscheats/
