Enter these codes at the character select screen, press "del" and enter the name. Spacing on the codes may or may not be right.

itsgallus: All Levels All Cities
nineinarow: All Levels All Cities
super well: All Levels All Cities
iamthelaw: No Police
stevesmates: No Police
itcouldbeyou: Gives You 999999999 Points
suckmyrocket: All Weapons, Armor, & A Get Out Of Jail Free Card
itstantrum: Unlimited Lives
6031769: Unlimited Lives
hate machine: Raises Point Values
buckfast: Press the * on the NUMPAD and get all the weapons
porkcharsui: Diagnostic Mode
callmenigel: Press * for all weapons
iamgarypenn: Extra offensive language mode
iamnotgarypenn: Disable extra offensive language mode