O'Brien revealed on his TBS late night talk show 'Conan' last night that he won the role via a charity auction.

The producers offered to write a character for O'Brien, but he declined. "I think it's much funnier if I'm in the bar, in the background," O'Brien said.

Watch the video of 'HIMYM' star Neil Patrick Harris' chat with O'Brien below.

Hat tip to Vulture for pointing us in the direction of this gem.