He also supposedly left a few seconds of film before he died that Mick Jagger of Rolling Stones purchased for several thousand dollars, not to mention likely several children born out of wedlock.
I don't believe his legacy stopped with him, but his offspring don't play music--not that they ever admitted to being his child.
I'm doubtful of the whole "crossroads" thing, but after disappearing to practice more and then reappearing with talent, he REALLY played off the rumors and made himself famous. The other part of the rumor (besides having been taken by the devil), is that a jealous husband poisoned him.
We'll never know, though; will we?
I want to take a trip down to what is considered the official spot of the crossroads where he supposedly sold his soul to the devil, but it's an interstate crossed by a city road now.