Various Codes
During gameplay type:
IAMACHEATER
The following cheats become available:
C - Add $10,000 every time you hit the key
U - Unlock all items (Unlimited)
S - End Mission
Here are some system options - the IAMACHEATER trigger is NOT needed:
CTRL+I - Toggle Interface On/Off
CTRL+NUM+ - Increase Gamma
CTRL+NUM- - Decrease Gamma
CTRL+[ - Quit Game