I have a friend who was asking me to help identify an arcade game, but I'm drawing a blank... He says:

I remember playing an arcade game years ago (10?) around the time that Heavy Barrel was out. It was a stand-up game. You looked at your character from directly above. You moved through hallways and rooms, You could avoid getting shot by flattening yourself up against the walls. The name was odd, one word, I think.
Any ideas?

I've asked him if it is sci-fi or military in nature; will see what else people think I should ask if someone doesn't know it.