According to Wikipedia, "Poor Boy, Long Way from Home" is a "traditional blues song of unknown origin." To my knowledge, it is the only song recorded by both John Fahey and the Rolling Stones (called "Prodigal Son" by the latter). I haven't been able to find many videos, but I figured that John Fahey and Bukka White made it worth posting. Lots of variations in the melody and words in the other cuts below.
Excellent posts, Steve!