US Air Guitar champ William Ocean minces neither licks nor words. So when he dubs his shredtastic gang of merry jammers the Greatest Air Band in the World, that world takes note. Out of the millions of bathroom-mirror rockers and shower singers, there could be only five, and Ocean presents them tonight on the eve of their nationwide tour. "Singer" Shreddy Mercury and Ocean himself front the awesomest band you'll never actually hear, complete with air drums, bass, keys, and horns — and the same noms de rock they've been using since eighth grade (Air to the Throne, anyone?). You'll find us headbanging backstage, drinking air beers with invisible groupies.