The other day, we had a moment when The Captain (our lead project manager) said "mush pot" and then I, among others, misheard it as "mosh pit." When I poked my head into The Captain's office to ask about the mush pot, he said it's part of a children's game.
So we get on Google for a quick bit, and we find "Duck, Duck, Goose." (Apparently called "Duck, Duck, Gray Duck" in Minnesota... and only in Minnesota) Some versions call the middle of the circle the "mush pot." The person assigning each player as "duck" or "goose" has to sit in the middle of the circle if the goose (chaser) successfully tags him or her.
The mush pot becomes a place of contemplation, a box seat, or a forced rest, especially as a tired person is more likely to be sent there, but most Duck, Duck, Goose participants would prefer not to get caught up in the mush pot because it is a passive, spectator role, and most first graders tend to be very participatory. As people grow up, perhaps the stigma of the mush pot wears off.
Funny we misheard it the way we did, because the complete opposite of a mush pot is a mosh pit – a rock concert phenomenon in which large groups of people jump, headbang, or body-slam near the front row. Numerous sites on the interwebs (such as this one) will say that mosh pits originated at punk rock shows of the early 1980s, and while none of these are connected to any formal surveys or research, most of them point to actual experiences or concert footage from that time period.
Here's a modern one that took place in Dresden at a Hatebreed concert.