Tyson checking his sig (and everyone else who came after him).
http://www.gofuckyourself.com/showthread.php?t=306053
The second most replied to thread that wasn't a contest.
http://www.gofuckyourself.com/showthread.php?t=172785
Which was a run for the 2 millionth post (which technically does make it a contest, though the thread wasn't started as one).