During Game play hold in Ctrl while entering a Code below.

If you do it right you will hear glass break.

Codes Function

atheist - God Mode
arm - Gives you full armor
hell - Gives you full heath
phish - Canges field view
blue - Map shows locations
godeye - Map reveals all locations of enemy (green dots) and objects (white dots)
asd - Super jump
woo - Gives you two pistols and all the ammo
freedom - Gives you two shotguns and all the ammo
xse - Gives you an m16 and all the ammo
axes - Gives you all access cards
medic - Gives your squad members full heath
chat - Makes squad members talk
nimrod - Makes squad member rebel against you
aslag - Gives you all weapons and ammo and full heath
oxy - Gives you full oxygen
vomit - Changes field view to 170 degree view
acid - Gives you infrared vision
klatu - Freezes all enemies
ksa - Kills squad member 1
ksb - Kills squad member 2
ksc - Kills squad member 3
ksd - Kills squad member 4
horse - Gives you all grenades
deth - Gives you rocket gun with ammo
tozt - Gives you a flamethrower
vent - Gives you a two machine gun with ammo
thrill - Gives all members all weapons
hdcs - Makes member go wild
phnx - Gives members full heath
qed - Complete mission objetive
ext - Makes area extraction zone
soia - Skip missions

Level Select:

Hold CTRL+ALT at the main menu to access the level select screen. Click on the arrow to choose your starting level.

Suicide Missions:

Hold ALT-M at the main menu.