At the Mission computer press ctrl+F1 .

Then You can enter one or more of the following codes. All the codes are case sensitive !!! Correct codes will be confirmed by a beep.

Here are the codes:

Redtop Trod - Select all single player missions from the mission Menu.
Half Libel - Activates Teleport key.
Had A Nude On - Activates Invincibility key.
Brass Clue - Activates Amunition Key.
Mother Mourn Us - Changes mountain on mission 1-5 to Mt. Rushmore with programers faces.
Chaste Coed - View the end video sequences.
Rotted Drop - Activates Destroy Target.
Horny Elk Leer - Activates all targets on radar key.
O'Sarge - Gives Seargeant in training missions an Irish accent.
Swiss Throat - Changes Citadel building into 7th level headquarters.
RANGE GOES GORY - All Levels, and lots of other stuff
DUNK IT HERE - Recording Session Outtakes
OH NO! LESS JAPAN - Activates Ion-Strike Key
A Scramble On - Let's you take screen shots by pressing [shift]-[ctrl]-[right-click].

In-Game-Keys :

CTRL+I - Activates Invinciblity
CTRL+Z - Refills ammo
CTRL+F - Destroy current target
CTRL+B - Teleport Behind Target
CTRL+P - All targets on radar

Photo Gallery

Type "Swiss Throat" in the cheat code box and it changes the Citadel building in mission 2-6 to 7th Level Headquarters and inside are the pictures of the programers. Hit TAB to cycle through them.

Pick a Ship

If you use a gashr on any occupied ship, the pilot will come out. If you go into its ship, it's yours.