Press F11 and enter these codes:

ISITWENTYShows all map
ISILETSBAILFinish the current level
ISIWHEELSGet access to the X-car! (you must finish the level to get it)
ISIFATPACKEDGives you all the weapons, ammo & powerups
ISIQGod mode
ISISLEEPFreeze your enemy 

Thanks to Revolution readers Pavel Spirine and Cory!