I've heard some great cello playing, and I've heard some great beatboxing, but I've never seen them together. Maybe in some sort of wicked mashup, but this is not a wicked mashup. This is one man, Kevin Olusola doing both at the same time. The song is called "Julie-O" by Mark Summer. It's a hell of a good interpretation and performance, I've got to give Kevin major credit for pulling it off to what I can only assume is near perfection. Hip-hop cello beatbox, enjoy.