Michael J. Fox was on Oprah to promote his book Always Looking Up, which chronicles his struggle with Parkinson's. His symptoms are much more pronounced now, but he's maintained optimism and a sense of humor.

He and his wife Tracy joked that their kids call him "shaky dad," and Oprah read a passage from his book (the name of which is an inside joke about being short), in which he describes the difficulty of doing everyday tasks like brushing his teeth. He said that the upside of his disease is that the uncontrollable, jerky movements turn any regular toothbrush into something that could rival the most powerful electric one.

And while he says that "vanity was the first to go" when he became symptomatic, it should be pointed out that he looks years younger than 47 (going on 48), despite his disease.