Hayden Panettiere. NBC.

Either Hayden Panettiere has a great sense of humor or she is a big idiot. When David Letterman asked her what it meant to become an adult, her response was clearly uninspiring, "But I think the only things I can do is buy cigarettes, porn and, if I get in trouble with the law, I'm kind of screwed." She also said that from now on she does not have to listen to her parents because she can now answer "You can't talk to me like that, I'm an adult."

Is that the kind of "Heroes" we want our Hollywood celebs to be? Clearly not. Thankfully, she added that being an adult also means that she can vote and she plans to register to vote.