This video has been just about everywhere, but even though I'm not a big fan of Sarah Silverman or Jimmy Kimmel, it cracks me up every time I even think about it. Matt Damon just comes across as very cool and a good sport for making it.
A little background for those not in the know. Sarah Silverman (comedian) is dating Jimmy Kimmel (talk show host). Kimmel has a running gag involving Matt Damon (actor)--this quote from that font of all knowledge, Wikipedia, elaborates:
Comedian Jimmy Kimmel often says: "Our apologies to Matt Damon, we ran out of time" near the end of his ABC television show Jimmy Kimmel Live, a gag lampooning instances where shows cannot feature their last guest due to time constraints. On September 12, 2006, after a segment highlighting the running gag and a lengthy introduction by Kimmel, Damon finally appeared on the show, only for Kimmel to apologetically cut his interview and head to credits, as Damon cursed him. Kimmel later confirmed to USA Weekend that the skit was entirely planned and Damon willingly played along.Anyway, here's the clip, from Jan. 31's Kimmel (it's probably not safe for work):
I think my favorite bit starts at around 2:45 on this clip, with the M.C. Hammer riff.