While most folks left Bonnaroo on Sunday, Robert Plant and Alison Krauss drew one of the festival's biggest audiences for a high-energy set that included mateiral from their debut collaboration Raising Sand. Plant kicked things off sans Krauss, running through tunes like "Rich Woman" with his backing band, which featured roots-rock legend T Bone Burnett. Plant also treated Zep fans to a rip-roaring rendition of the classic "Black Dog," shrieking and tossing his microphone in the air. Once Krauss joined him onstage, things got progressively more country-fied, with Krauss adding masterful fiddle lines to eerie tunes like "Sister Rosetta Goes Before Us." The crowd was delighted, as was Plant. "Welcome to our little world," he said. "It's a great pleasure to bring this gift. It's been a wonderful time for you and me."