It's quite an honor to have a movie made about you while you're still alive to enjoy it (it certainly helps if you wrote the book). But how intimidating it must be for the actor who must portray you! Quite a few films not only tell the story of someone who lived it, but that subject is sometimes on the set, and even in the film itself. It's usually a small part, or even a cameo just walking through the background, but if you pay close attention, you'll get a kick out of spotting them. Check out a list of these movie appearances by a biopic's subject at TVOM.