You know what, you really don't want to miss out on this video. I promise you that if you start watching this guy, you will not be able to stop. Be sure to watch it all the way to see the short interview with him. He died a few years ago, RIP Denny.
What he does: Turns on a song, lets say "Layla" (which is actually on this video) then paints the artist, in a matter of minutes! YOU HAVE TO SEE IT to believe it!