Bobby McFerrin is a talented jazz musician who has recorded and performed with artists such as Chick Corea & Bela Fleck… Sadly he’s pretty much just known for the song Don’t Worry Be Happy.
In this nifty video McFerrin trains the audience, and turns them into a giant musical instrument over the course of about three minutes. And he does it without giving a single verbal instruction.
McFerrin has performed this same musical experiment all over the world, and there are plenty of YouTube videos to prove it. It seems that the pentatonic scale is culturally universal, and intuitively understood by humans the world-over.
Musicians like the pentatonic scale because it’s impossible to play an incorrect note with it.
If this interests you, Intellectual Pornography has a more extensive analysis.
The Geek Whisperer 
Pure genius.