Last one to post in this thread wins!

Back about 40 years ago when I was a couple years in the mechanic field working at Kmart Auto I had the hood open on a late 70`s Ford truck. When I went to start it the battery blew up and soaked everything under hood and the mechanic next to me. Lucky it was on his back and not his face. The whole battery top was gone and the cables still hooked to the standing plates.

wtf CF? Any idea what happened? Must have been a spark but should have been vented with the hood open.