Stonefly Brewery, 9 p.m. As goofy as it sounds, with the popularity of the U.S. Air Guitar Championships, competitions like this one are popping up all over the country. It’s easy enough to understand the appeal: They let contestants feel like rock stars without actually having to master that pesky “rock” part. Plus, they’re kind of funny to watch. The act may be silly, but the contest isn’t a joke: The organizers have laid out strict rules and judging criteria on their MySpace page, www.myspace.com/airguitarshowdown. At this point, it’s only a matter of time until some ESPN channel begins broadcasting these things.�