Three beachballs get tossed into the audience, who bounce them around the venue (caution tapers!) and the band plays along with them: each one plays what a ball does. If, for instance, one of the balls gets grabbed and held by the crowd, the musician who is "playing" that ball holds the note. When it bounces around, they hit notes appropriately. At the end, they form a circle with their arms at the front of the stage and the audience bounces the balls toward them, into the circle, and then cheers.

They can bounce the ball hard or hold on. Sometimes people deflate them. We make a sound for that if the balls disappear and a different sound if they reappear. People figured out if they don't throw them back, we won't stop playing. So Mike and I and Brad, one of our road crew, form a basketball hoop with our arms. And they throw them back." -- Trey, Associated Press, 7/3/94

The first one was 11-19-92 II (St. Michael's College, Colchester, VT), not at the 2/3/93 Portland (Maine) Expo show, as Trey reported during his 10/24/02 solo show there, although that (2/3/93) was the first show with a piano.