Virtuoso acoustic guitar player with a signature, uncannily fluid picking style and, my, what a voice. Life fenced 'round with tragedy - blinded as an infant because of improper postnatal treatment (or so I've heard him attest), son Merle died in a traffic accident at age 36.
Take your pick of great songs - the finger picking intro to "Sitting on Top of the World," crystal clear flatpicking on traditional folk tunes like "Little Omie Wise" and "Shady Grove," mesmerizing vocals on St. James Infirmary and acapella spirituals. I think it's Merle who plays Banjo on Honey Babe Blues, and I can listen to the breaks in that song over and over again. And over again.
There are other great guitar players aplenty, of course, but we shall not see his like again.