Borderlands

Borderlands cheat codes: 
Edit the "WillowGame.ini" file in the directory:
"\..\Borderlands\WillowGame\Config"

Change the value of the following lines in that file to activate the cheats.
Cannot drop below 1 health point:
Set "bDemiGodMode" to "true"

Weapon slot capacity:
Set "WeaponReadyMax" to 2 to 4

Increase maximum inventory
Set "InventorySlotMax_Misc" to a higher number

Shoot own teammates:
Set both entries of "bIgnoreFriendlyFire" to "false"

NPCs can damage each other:
Set "bIgnoreNPCFriendlyFire" to "false"

Bosses do not regain health after dying:
Set "bBossesRegenHealthOnReset" to "true"

Resurrect all players when someone dies:
Set "bResurrectAllPlayersWhenOneDies to "true"