http://www.youtube.com/user/AndyRehfeldtIf you haven't heard of him, that's fine. He's a musician who takes existing songs and changes their style dramatically, for no other than his own amuesment. Unlike most musicians on YouTube, he performs and records all the instruments, and sometimes will sing.
An example; Behemoth's Demigod turned Radio-Disney style.
Especially at 2:46, Hail Santa!
Another example, Lady Gaga, turned Metal.
Like the highest rated comment says, it's also fitting because her band looks like they would play metal.
Hope you enjoy!
Cinco de Mayo