Biting Baby

I know I'm having a bit of a posting binge, but I've got one more thing: do any of your mothers out there have some wisdom about teaching a baby not to bite? My little one seems to find biting to be quite a delightful activity. He'll bite anything: a hand, a leg, a neck, you name it. At first I tried yelping, then I tried giving a little spank, then I tried looking at him sternly and saying, "No." He found all of these responses amusing and thought that we were playing a little game. So then I tried setting him down of the floor away from me, but he didn't seem to notice that it was a punishment. These days I mostly just detach him as quickly as possible and tell him in a very calm voice, "Don't bite. It's not nice." But the biting persists. Any ideas?