I recently came across this Kutiman project and it blew me away!
This cat is mindblowing! Kutiman basically took a mass amount of youtube videos, of instrumental or voice related and chopped them up, producing them into tracks.
He then made videos for each track, using the YouTuber's clips... not only brilliant, but these tracks are sick. Go right to track 3! Wait for the beautiful voice to kick in, then the freestyle... amazing.
Click here for his home page.