One of the best new threads started in 2005 would have to be
Fortunately/Unfortunately. The situations generated there are already legendary. I think most of you have noticed
Hookbill's Mount Zoom insanity by now, and
Gil-Galad enjoyed playing around with Johnny the Stinky Balrog for quite a while there. There was also a great deal of uncloaking on Gandalf's part.
On a sadder note, I mourn the (hopefully not permanent) loss of Boromir the Disco King, a subject first brought up by
Oddwen way back in (I think) 2003.