So the show is going along, they do the opening segment, commercial break, second segment, Jon Stewart starts talking about the new term that's been going about the news, "staycation," used to refer to people who are staying home for vacation because they can't afford to go anywhere. Then John Hodgman comes out and joins him to do a segment about it. He gets to the end and says he's going to do a song, and starts singing something about the rooms of his house to the tune of that "i've been everywhere" song from the hotel commercials. But as he's starting this Jonathan Coulton walks onstage playing the music to the song! They didn't say anything about him at all, or have him do anything else on the show, that was it. I checked the Jonathan Coulton website and there hadn't been any announcement of it ahead of time, but he did do a Twitter post after the show was first aired last night confirming that it was in fact him.
Clearly Jonathan Coulton and John Hodgeman have something going on. Possibly a nefarious plan to take over the world, i don't know :) Speaking of which, ceph, do you remember if the audiobook you have of "The Areas of My Expertise" is unabridged or not? And if not do you remember about how long it is or how many CDs it took up? They have a copy of it on Audible but it's abridged. I'd like to get it for the Jonathan Coulton bit but i don't want to get that one if there's a longer version out there somewhere.
Anyways, if i've navigated the Daily Show website and copy/pasted properly this should be the segment in question :)