What is it about celebrities in (Photoshopped) Christmas sweaters that warms our cold little hearts? Maybe it's the fact that everyone, no matter how famous, looks hilarious in knit tops with embroidered poinsettias on them. Take a look through our gallery of musicians in their Xmas finest, and see who rocks it best. We vote for Christina Aguilera, mostly because we don't think anyone else could wear that hat and get away with it.