Gnarls Barkley is truly a musical phenomenon. The kind of tunes that Danger Mouses Brian Burton and Cee-Lo Green have been churning out over their two album career could find a spot in the hallowed halls of Motown or Northern Soul, hip-hop, pop or even alongside some of the indiest of indie rockers on the planet. The duo first rose to international fame when their song Crazy was released in 2006. Cee-Los powerful pipes had everyone humming along to the haunting, yet totally danceable, cut. The following year, Crazy picked up a Grammy for Best Urban/Alternative Performance and the album it came from, St. Elsewhere, netted Best Alternative Music Album. As impressive as they are in the studio, though, live is where Gnarls Barkleys genius really takes flight. The movies Star Wars, Superman, A Clock Work Orange and The Wizard of Oz have all provided onstage costume inspiration to date. We have no idea what outfits theyll don for their ACL Festvial set this year, but we can confirm it will be packed with terrific songs old and new, like Run, from their sophomore album, The Odd Couple, released in March.