Duke Nukem 64

DNSTUFF- All weapons, ammo, and key cards.
DNITEMS- All items and key cards.
DNHYPER- Steroids.
DNSCOTTYel-Level warp(where e is the episode # and l is the level #).
DNMONSTERS- Monsters will disappear as soon as they see Duke.
DNCASHMAN- Makes duke throw money then you press the space bar.
DNRATE- Displays frame rate
DNBETA- Displays message: Pirates Suck!
DNCOSMO- Displays message: Register Cosmo Today!
DNALLEN- Displays message: Buy Major Stryker.
DNVIEW- Chase plane view.
DUKE NUKEM 64 THE ULTIMATE CODE

At the password screen, enter:
W93M 7H20 BCYO PSVB
This will give you 100% health, 200% armor, all weapons, full ammo, the backpack, 3 pentagram(?)items for your laser, and levels 29-31 complete.