I'm clearly a fan of McFerrin, although I couldn't tell you when the first time I heard him was. What gets me is that when he speaks he's a baritone, yet he can sing something like four octaves. His range is both higher and lower than mine. I only wish I could make the sort of sounds he does. Also, he is not stupid by any stretch of the imagination and I admire his intelligence and depth of knowledge.
Since I now know there's a few fans,
here's an example of Bobby doing a bit of audience participation. This is why seeing him live is on my list of things to do, although I unfortunately have not had the pleasure yet.