Madness interactive cheats
the best is the cheats:
Here are the cheats and what they do:
apollo: All enemies use explosives.
hop: jump good~!
arnold: pumped up (for hitting people)
armstrong: reach doubled
newyorkminute: infinite bullet time
willis: god mode
gump: run (combined with arnold and bullet time makes for a nice neo effect)
minnie: ammoless machine gun
flcl: (fooly coolly!, an anime by gainax.) unlimited ammo
Guardian Angel 
Domo-Kun Angry Smashfest! 
Megaman - ProjectX(demo)