Must be entered in the Faction menu, after pressing Select, and you'll get a confirmation sound if Code was entered Correctly.

Code	Effect
Right, Down, Left, Up, Up, Left, Down, Right	$1,000,000
Right, Left, Right, Right, Left, Right, Left, Left	Infinite Ammo
Press Up, Down, Up, Down, Left, Right, Left, Right	Infinite Health
Up, Up, Up, Up, Down, Down, Right, Left	Reset all factions to neutral