Wouter "Wally" De Backer (or Gotye, as you may know him) noticed the "mountain of interpretations" of his song Somebody That I Used To Know on YouTube and decided to do something about it.
No, he did not issue take down notices. Instead, he decided to create a remix of remixes, and the result is quite epic. See for yourself - Here's Somebodies: A YouTube Orchestra. (He even listed the links to the covers on his blog)