Bill Cosby Dances, Mocks His Old Age in Spirited 'Letterman' Appearance (Video)

Bill Cosby on David Letterman - H 2013

Bill Cosby on David Letterman - H 2013

No sweater, no problem.

Bill Cosby delighted the audience at the Late Show on Tuesday night, dancing to the theme song of the Harlem Globetrotters (in a way quite reminiscent of his old sitcom routine), delivering some stand-up comedy (while sitting down) and riffing on his old age, among other punch lines.

Yet for all his jokes about dementia, he's clearly a spry 75; not only can he spend half his time slot dancing, he's also still on the road, playing theaters and clubs in much the same way Jerry Seinfeld has continued to barnstorm after his hit TV show went off the air.

While Cosby wore a blazer, crisp shirt and suspenders on Tuesday, those who want to relive his past sweater glory can vote in his tournament of sweaters on his website. Vote or die.