Codes from Source Engine
     Press  the  Console  button  (default  is  '/~)  and  type in the
following codes:

Cheat code:                       Description:
ship_security_disable 0/1         Disable/Enable all security
ship_give_all_weapons_shoot       Give all guns
ship_give_all_weapons_stab        Give all stabby weapons 
                                  (swords, syringes, etc)
ship_give_all_weapons_slash       Give slashing weapons (razor, etc)
ship_give_all_weapons_bludgeon    Blunt weapons
sv_noclipspeed 0.5                Lowers noclip speed 
                                  to normal walking speed
noclip                            Fly through walls and levitate
buddha                            Invincibility
mfk_min_value number              Change minimum money awarded for a kill
bot_kill                          Force all bots to immediately suicide
ship_enable_bots 0/1              Turn bots on or off
sv_cheats 1                       Enables cheats
noclip                            Do not collide with walls and objects
god                               Invincibility