While in the game, bring up the console by pressing [Tab]. Now, type in
 any of the following for the desired effect:

 GIVE ROCKETL            -  Gives you a rocket launcher
 GIVE MINIGUN            -  Gives you a minigun
 GIVE NAILGUN            -  Gives you a nailgun
 GIVE PULSERIFLE         -  Gives you a pulserifle
 GIVE HEALTH             -  Gives you full health
 GIVE ARMOR              -  Gives you 100 armor
 GIVE AMMO1              -  Gives you bullets
 GIVE AMMO2              -  Gives you nails
 GIVE AMMO3              -  Gives you rockets
 FPS                     -  Displays the framerate
 FRAMESYNC               -  Toggle framesync ON/OFF
 GOD                     -  Toggle god mode ON/OFF
 QUIT                    -  Quits the game