David Letterman didn't retire after 'Late Show' ended in 2015. Discover what the talk show legend has been up to, including new projects and appearances ...

Indianapolis native David Letterman was a big fan of the "Greatest Spectacle in Racing" long before he became a TV star or an IndyCar team owner.

DAVID LETTERMAN: I understand you're leaving the show. CASHMAN: I'm leaving the show, yeah. LETTERMAN: I have a couple of thoughts, a couple of things to say. First of all, are you certain? Are ...

SUMMERS: Now, we actually have some tape from that episode where David Letterman came to your show. I know that aired last weekend. We'll play it. (SOUNDBITE OF TV SHOW, "THE NITE SHOW") DAVID ...

Letterman first and foremost, Johnny Carson - I somehow found after I found Letterman - and Conan are the three pillars for me for late-night talk show people. And I try to emulate them. So in the ...