Two titans of comedy switched roles and the results were gut-busting.

David Letterman was the guest on the most recent episode of Jerry Seinfeld's acclaimed Web series 'Comedians in Cars Getting Coffee.' Usually, Letterman is the one asking the questions on his late night show, which made this encounter all the more interesting, since he rarely gives interviews.

The stars, both of whom are car connoisseurs, headed out in a 1995 Volvo 960 station wagon. The soccer mom-mobile is surprising, yes, but the coolness factor is ratcheted up by the fact it has a 380-horse power racing engine inside, given to Letterman by the late Paul Newman.

A haggard-looking Letterman talks about getting stranded with his father-in-law in the car after it died, the perils of following Richard Pryor and the time he stopped by the set of Seinfeld's sitcom.

They pull into a coffee shop, where, among other things, they talk the rules of football, Letterman's love of hardware stores, parenting techniques and Letterman's early days in standup.

Oh, and, yes, Letterman does make sure to whip out his Jay Leno impression. C'mon, you knew he would.