49. Joan Rivers
She was cracking wise, working blue, and crashing comedy's stag party decades before you were born. Now, at age 79, Joan Rivers remains inimitable, and more surprising, vital. She's got regular gigs on E!'s Fashion Police and her reality show Joan & Melissa, but she's at her best – and most jaw-droppingly offensive – when at her regular stand-up gig at a basement nightclub near New York's Port Authority, performing a live-wire act that would make Andrew Dice Clay blush. Rivers played herself on an episode of Louie, dispensing wise-old-woman comedy advice, and throwing Louis a charity roll-in-the-hay for good measure. He wishes.