I wish I remembered! I just don't. It was when you couldn't join though, and that made me SO SAD.
Proving the power of the internet
My favourite memory was when I used AskMeFi to instantly prove the amazing power of the internet and this extraordinary community to a Luddite friend who desperately wanted a particular song for her grandfather's 100th birthday. She had looked high and wide, and googled madly.
Metafilter gave it to her in an hour.