Here's a fun sampling of some of the "unscheduled" performances:

Buskers, Briefly, from Doug Plummer

Doug's a great photographer (known in the contra dance scene) who's having fun getting into digital video. Check out his other stuff on that site (including two great timelapse films of the dance floor going down and coming up), and also on his main site, dougplummer.com.

~ Becky in Tucson
(thought I spotted him there, but wasn't sure at the time...)