Back in the BWL days there was a bug with Burning Adrenaline (
http://www.wowhead.com/?spell=23620 ), the debuff Vael would put on 1 player at a time. Pets could get BA and then be dismissed. We had a warlock pet get BA once, and the person reacted in time to dismiss the pet before he blew up. As soon as the raid was over the entire guild went into the IF AH (only AH was in IF) and the pet was resummoned.
Imagine being in the AH checking auctions and suddenly everyone is hit for ~5k fire damage, a lot of damage in those days. I'll see if I can find the video a guildy made of it, got some good forum drama out of it too. Blizz fixed it shortly after though.