Best Viral Videos 2010: Lip Sync Kid

Keenan Cahill, at just 15, became a viral star last year with his series of badly lip-synched videos he recorded from his bedroom. He's now graduated to full-blown celebrity, 50 cent recently stopped by to record a video with him. But his best video is still Katy Perry's "Teenage Dream". We just wish Keenan would clean his room once in a while.