The funniest thread I saw here was a couple of days ago, Wednesday I think.
Some guy posted in the lounge about how to turn $5 into $20 000. It was spam, naturally, but it was so funny. It covered about a page and a half on 1024x768, and in the middle it said "DO NOT LAUGH" and continued with more spam.
It got deleted, unfortunately. It was sidesplittingly funny just because of the spammy nature of it.
Master of common sense. If you don't like it, stop reading.