Note: If the console does not come up, open the [install directory]portalcfgconfig.cfg file with Notepad and make sure conenable is set to "1".
Code - Result:
svcheats 1 - Enable Cheat Mode
svcheats 0 - Disable Cheat Mode
aidisable - Toggle Enemy AI
buddha - Player Takes Damage But Won't Die
god - God Mode
hurtme - Decrease Health by
impulse 101 - All Weapons and Ammo
noclip - No Clipping Mode
notarget - Invisibility
matwireframe 1 - Wireframe Mode
svnoclipduringpause 1 - No Clipping During Pause
svinfiniteauxpower 1 - Unlimited Auxillary Power
showtriggers 0 - Show Trigger Brushes
Unlock All Chapters:
Modify your [install directory]portalcfgconfig.cfg file with Notepad and change svunlockedchapters to "11".