Are you talking about Zach Galifinakis?
This is, by far, my favorite Michael Scott moment. Basically, Michael buys a house for his girlfriend, who is also his boss, and realizes that he can't afford it. Jim convinces him that he can declare bankruptcy by simply telling everyone.
No, the dude that played the dentist in the Hangover, and asked that blonde chick out via conference call singing Abba "Take A Chance on Me." The guy who went bugshit when Dwight applied to Cornell.
Last year, I watched a marathon of episodes of the English version, and while they were hilarious, the American version is a different kind of hilarious.