Blue Man Group is a great show. If you haven't already seen it, get there!
These are the guys you used to see in the Pentium advertisements on TV, with faces painted all blue. The theater is very small. If you're really brave, sit in the front row. They give you a rainjacket on your seat so you're protected from some of the items that might otherwise get you wet or dirty. (It's all ok!)
They randomly pull one or two people on stage and that's fun to watch. The music they make from the various appliances is pretty amazing - it's just 3 guys putting together random sounds, objects, and sites to make artwork and entertainment.
Definitely worth the money!