If necessity is the Mother of invention then spite is the Mother of the Tooth Golem.
This is what happened. After a 4th ed. encounter my players were looting orcs or hobgoblins or something. For some reason while I was trying to add some local color I let slip that the baddies had a few teeth in thier pouches. I'm not sure why, doesn't matter. A few of the players pocketed the teeth or attempted to glean to what creatures the teeth belonged. While others, with blatant disregard for the Gods of Roleplaying, threw the teeth away. That kind of made me mad. I'm not sure why, doesn't matter. So from then on, just about every baddie they faced had some teeth in their pouch. It became a game within a game. I give teeth, certain players keep them and certain players throw them away. At first, I didn't know how I was going to exact my revenge. But over the months a devious plan fomented in my puny DM brain. I tweaked the stats for a chain golem [hat tip Wotcs' Monster Builder] and made it so that if you threw teeth into one of it's many maws it would leave you alone but if you had no teeth you were doomed. I did pull up short of a partial party kill, but I hope I made my point.