Each morning, for the past week or so, as we stagger westward along Sunset Boulevard, we find ourselves passing under not only the hot June sun, but also a second artificial light: the marquis at The Key Club. Of all the images that blast out from its screen, one continues to raise our eyebrows: The U.S. Air Guitar Championships, which will be held there tonight. The victor will be sent to New York's Irving Plaza Fillmore for the August 16 National Finals. The national champion then has the opportunity to compete in the September World Championships, which will be held in Oulu, Finland. So yeah, that's happening.