One of the best shows I ever saw was Mutemath playing Stubbs. It was inside, and though it was packed, it couldn't have been that many people. I'd heard of them from a friend but hadn't gotten their debut album yet, but I knew I was in for a treat when the drummer came out and began duct-taping his headphones to his head. It was soon apparent why....the guy flailed around so much while playing that they would've flown off in the first three seconds otherwise.
Holy cow, those guys could play. I got the album, and I like it, but it's one of those things where if you ever saw them live, the albums can only disappoint you.