What's it like to have one of the world's biggest music superstars sitting on your shoulders?  Ask LMFAO's Redfoo -- he was the one carrying Madonna around during her halftime show on Super Bowl Sunday.  "I don't know how many people were in the stadium, but they didn't exist," Redfoo says in the new issue of Rolling Stone magazine.  "All that existed was me and Madonna." Redfoo also reveals that Madonna busted on him for having difficulty lifting her up.  "In rehearsal, she said, 'If you were working out more, you could lift me a little easier,'" recalls the musician, whose birth name is Stefan Gordy.  "Her biceps were way more cut up than mine.  She was like, 'Get a jump-rope.'"Overall, Redfoo says that for LMFAO, working with Madonna was the ultimate dream.  "If Michael Jackson is our number one, Madonna is the number-two inspiration for everything LMFAO does," he tells Rolling Stone.