Press [~] to open the console and enter one of the following commands:

god - Toggle God mode
version - Return game version
map <map> - Load another map (see further on for possible maps)
mapcomplete <map> - Mark the map as completed (putting you at the next map)
noclip - Toggle walking through obstacles
respawn - Toggle monster from respawn
monster - Turn monsters off
developer - Toggle developer mode
record - Start recording a demo
stoprecord - Stop recording a demo
play - Play a recorded demo
stopplay - Stop playing a recorded demo
musictrack - Change the current playing musictrack
prestrack - Last music track played
drawface - Toggle drawing of texture faces
drawtris - Draw the map sections
drawgun - Toggle the drawing of weapons held
drawone - ?
drawportal - Toggle Outlining of portals and doors
drawnormal - toggle Draw wall normals
pview - Toggle 3rd person or static view
drawbound - Toggle highlighting of bound objects
drawcell - Toggle highlighting of individual cells
fov - Change the field of view
jumpstep - Change the jumpstep value
groundacc - Accelleration speed on ground
groundslow - Slowing speed on ground
gravity - Gravity
exit - Quit the game
maxspeed - Maximum moving speed
airacc - Acelleration in the air
airslow - Slowing in the air
soundsys - change current used sound system
bombslow - Speed at which bombs slow
musicvol - Ingame music volume
soundvol - Ingame sound volume
autoswitch - Toggle autoswitch weapons mode
fullscreen - Toggle between full screen or windowed mode
colordepth - Change the current bitdepth
videomode - Change the current videomode
bms - Change bms?
bmd - Change bmd?
statutbar - Toggle the HUD display
animspeed - Animation speed
lightmap - Toggle lightmapping
cullface - Toggle backface culling
renderent - Toggle rendering of entities
directstart - Toggle direct start?
eps - Change eps?
offset - Change offset?
leaf - Change leafs?
noscript - Toggle the scripting in the engine on or off
resetgame - Reset internal game state
saveconfig <file> - Save current config to file
loadconfig <file> - Load config from file
picmip - Change amount of offset pixels during mipmapping
gamma - Change gamma
drawfsp - Show framerate, set to 1 to turn on
invertmouse - Invert mouse control
cvel - Change cvel?
pvel - Change pvel?
prvel - Change prvel?
plook - Change plook?
killdepla - Amount of Depla's killed
killmorba - Amount of Morba's killed
killzeubat - Amount of Zeubat's killed
killsubzerat - Amount of Subzerats killed
killzemummy - Amount of Zemummy killed

Possible maps to use with the <map> commands are:

h1m0
h1m1
h1m2
h1m4
h1m5
h1m6
h1m7
h1m8
h1m9
mapbonus1
mapbonus2

by n0N4M3/TR3iBJ4GD, michaillegov@hotmail.com