Cougars are cute, and ingenues are great, but there's nothing like the coquettishness-meets-experience sex appeal of a woman in her thirties. Let's salute the dirty decade with a list of the top 10 nude celebs who turn 31 in 2011, like Christina Ricci, Eliza Dushku, and Michelle Williams.

Sorry, Jessica Simpson. Get naked, and maybe you'll be on the list!