Whats the biggest mosh pit you ever been in and what band had it?!

Whats the biggest mosh pit you ever been in and what band had it?

I've been to a Slayer concert in 2000 ... that concert was absolutely nuts. I read the next day in the paper that four dozen people were taken to a hospital for injuries relating to being trampled and stuff. The mosh pit wasn't just one area, it was the entire building! While thinking of it as awesome at first, I vowed never to go to a heavy metal concert again.