Rock Star Style at Christmas

John Parra/FilmMagic
Like many pop sirens, Perry took the sexy Santa chanteuse route when she performed at Y100's holiday concert spectacular in 2010. To keep the look distinct, she gave it her own cartoonish twist: that red velvet, fur-trimmed skirt is a bit flouncier than it needs to be, but Perry wouldn't have it any other way. And neither would we.