1) Apples, onions, zucchini, and a loaf of bread--from vendors and customers when we were playing at an outdoors farmers' market in Decorah, Iowa
2) One slightly used Dum-Dum lollipop--from a small child at said farmers' market
3) Extra musicians--I and two friends of mine were playing at a street fair in Missouri (on banjo, mandolin, and guitar) and suddenly every grandfather in town who owned a guitar wanted to play with us. I guess they were just glad to see twentysomethings playing old-time music, but soon we had a banjo, a mandolin, and five guitars, including one extremely loud twelve-string Martin. None of us were playing the same tune/rhythm/tempo (because we couldn't hear each other above the Martin) and I've never heard such a racket before, but at least all the Grandpas had a good time.