Press F11 and enter these codes:

ISITWENTY	Shows all map
ISILETSBAIL	Finish the current level
ISIWHEELS	Get access to the X-car! (you must finish the level to get it)
ISIFATPACKED	Gives you all the weapons, ammo & powerups
ISIQ		God mode
ISISLEEP	Freeze your enemy 

Thanks to Revolution readers Pavel Spirine and Cory!