Sore feet.
And a helium tank that weighs as much as I do in the trunk, waiting to be returned for deposit.
I might volunteer to do this again next year, but we'll see how I feel about it in the morning.
My thanks to Vogon, who suggested renting said helium tank, carried it across the school for me, and then inflated six dozen 12" balloons for me to clip three to a length of curling ribbon, taking over an hour out of his day to make my work decorating for an event easier.