Beyoncé doesn't just run the world. She runs USC, too.The pop star caused a frenzy when she was spied on the USC campus, apparently practicing her upcoming Super Bowl performance, LAist reports . She will be joining Coldplay for the halftime show.Students told LAist that Bey's unexpected appearance drew hundreds of onlookers, who surrounded her Escalade. The singer briefly waved as she left rehearsal at John McKay Center and climbed into her car.Needless to say, several fan videos and photos have surfaced.