Didgeridoo, aka "Yidaki"

The didgeridoo is considered the oldest wind instrument known to man. It's one of few instruments that uses circular breathing as a regular technique. It's hard to describe how it sounds. I'd recommend checking out sound clips on Didgeridoostore.com. It's the only instrument that I know of that can harmonize, vocalize, circular breath, and tongue roll all at once. Truly amazing! There is a steep learning curve, especially when learning to circular breathe. It takes lots of perseverence to get it right, but when you do it's truly is a rewarding experience (you will be part of 3% of world population who can circular breathe). I've also read an article that talked about how playing the didge can cure/prevent sleep apnea. Speaking of versatility!