I'd have to say for me it was waaaaaaaay back when Gianthold was still kinda new and they were doin a +1 Loot weekend.
2 guildies had had a late night and one crashed over at the others house. So in guild chat I asked "So how did the sleep over go?"
The other guildie responded"Great I shaved his back and we cuddled all night."......that in itself is funny. But instead of guild chat he replied in party chat.
We were in a PUG PoP run....there was a brief moment of silence(which seemed alot longer to my friend I'm sure) and one of the PUGGERS simply said....."Well.....that isn't somethig you see everyday." Very deadpan.
I laughed so hard I cried. My friend tried explaining himself....but he got drowned out by everyone laughing. He doesn't play anymore.....but when we still talk that incident comes up ALOT!!