I'm so happy when my Itunes decide to play such a great music!

According to a legend known to modern blues fans, Robert Johnson was a young black man living on a plantation in rural Mississippi. Branded with a burning desire to become a great blues musician, he was instructed to take his guitar to a crossroad near Dockery Plantation at midnight. There he was met by a large black man (the Devil) who took the guitar and tuned it. After tuning the guitar, the Devil played a few songs and then returned it to Johnson, giving him mastery of the guitar. This was, in effect, a deal with the Devil mirroring the legend of Faust; in exchange Robert Johnson was able to create the blues for which he became famous.

http://en.wikipedia.org/wiki/Robert_Johnson_(musician)