Cheat mode:
Press T and enter one of the codes:

Result - Code:

All weapons and items - idaho
All items - montana
Allow two of same weapon - bunz
All items - satchel
100 % health - clarice
200% health - spork
200% health, on fire - krueger
200% health, diving suit - cousteau
200% armor - griswold
Level skip - calgon, mario, or luigi
Level select, cheats disabled - spielberg
Temporary blindness - sterno
Invisibility - onering
Display framerate - rate
Suicide - edmark or kevorkian
Suicide by fire - mcgee
Drunk mode - jojo
Higher jumps - funky shoes
All keys - keymaster
No weapons, 1% health, drunk - fork broussard
Toggle clipping mode - eva galli
Full map - goonies
God mode - mpkfa, cap in my ass, I wanna be like Kevin
Temporary God mode - voorhees
Disable God mode - no cap in my ass
All weapons, ammo - lara croft or hongkong