Cheats for Quake 3

Unlock all levels at Skill 1:
Bring down console and type: /IAMACHEATER.

Unlock all levels at Skill 100:
Bring down console and type: /IAMAMONKEY.

Multiplayer cheats:
In order to use the following cheats in multiplayer mode, the server must have cheats enabled (that is: /devmap +map [name])

God mode:
Bring down console and type: /GOD.

All weapons:
Bring down console and type: /GIVE ALL.

NoClipping Mode:
Bring down console and type: /NOCLIP

More items using /GIVE:
Type /GIVE followed by the following codes to receive the corresponding items:

HEALTH
ARMOR
AMMO
PERSONAL TELEPORTER
QUAD DAMAGE.
BATTLE SUIT
FLIGHT
INVISIBILITY
REGENERATION
HASTE
BFG 10K
GAUNTLET
GRAPPLING HOOK
GRENADE LAUNCHER
LIGHTNING GUN
MACHINEGUN
MEDKIT
PERSONAL TELEPORTER
PLASMA GUN
RAILGUN