Apparently he bet a friend that if the Patriots lost to the Ravens he'd wear a dress on Letterman.
As we know, the Patriots lost.
So tonight, well...... damn.
I'll leave it to one of our sleuths to find a picture/video.
EDIT
Here's a link to a story, complete with video.
http://www.huffingtonpost.com/2010/0..._n_422673.html