Oh, this is the description for the surprise act on Incubate...
www.incubate.org
I don't know who it is, but Incubate doesn't book big names, plus the venue they're playing is really small. The extravagant costumes/public participation thing makes me think of bands like Caroliner or Fat Worm of Error, but they can't be it because they don't have any albums that are classics/evergreens that have entered the public canon.