A few years ago I heard of this artist Gotye and had to download his album Like Drawing Blood from some online mp3 site in Russia because it wasn't released in the US. Don't worry. I paid for it. And as best I can tell it was legal.
Not sure how this song of his new album Making Mirrors became THE song to cover, make a video of, and post it on the interwebs but hey...it's a fantastic song and these are some stellar covers. Check out Gotye's stuff.