Somehow managing to survive working on the bar at a busy ale festival for 10 hours straight (with maybe 30 minutes break in total during that time), from 2pm 'til midnight, followed by another 3 hours helping with take down - dismantling the stillage and getting rid of all the empty casks, cleaning up, etc. I felt like I was on the verge of collapsing by the end of it, and my feet still hurt now, afternoon on the day after. On the plus side, it was a big hit, and it's looking like we almost certainly broke even, and hopefully made a profit, so hopefully it was all worth it.
There's a good chance I'll be pretty much in charge of running the whole thing next time too, so I'll be there even longer if that happens. Yay.