I've got a third leg for you right here!
Magician’s 3-Legged Magic Performance

This is a clip from Penn & Teller: Fool Us of magician Axel Adler performing a three-legged routine, with each leg appearing to be an actual, functional leg. Of course one isn’t. Or maybe the trick is that all three are actually bionic legs. Regardless, I have three legs myself, you know. “You’re talking about your pe–” Yes I am. If it touches the ground when you get out of bed in the morning, it’s a leg, I don’t care what the biology books say. And don’t even get me started on that new math.