Cheat Mode:
During play, press 'Enter' on the Keypad to bring up the console. Now enter any of the following:

superman       God mode        
teamsuperman   Team God mode    
shadow         Invisibility   
teamshadow     Team invisibility   
ammo           Unlimited ammunition   
refill         All inventory items 
run            Run faster  
god            Get dropped on from a great height
  

Thanks to Revolution reader John Law !