USA TODAYIt's our top ten list: quotes from Letterman's last 'Late Show' everUSA TODAYIf you're of a certain age, David Letterman has been a constant in your life – as much of a certainty as death and taxes. You might've even imagined what it would be like sitting in the chair next to him on The Late Show, telling jokes to make him laugh as he ...Which Celebs Showed Up For David Letterman's Final Top 10?E!