Legendary Late Show host David Letterman is calling it a career this week, so it's a good time to look back at when one of our favorite Halos made it on to his show.
David Letterman was a goofy pioneer in the late, late talk show game, carving out a space on NBC for his own brand of wacky and off-kilter humor that wasn't really a staple of comedy as it is these days. He may have grown stale, boring or grumpy over the years, but really, he just grew old. It happens to the best of them, and he's decided to call it quits and become a insanely rich hermit, the same way his hero Johnny Carson did all those years ago.