I have seen a guy play a guitar one-handed. It is on the BET-Jazz music channel on my local digital cable system. He just touches the strings and the guitar makes noise-no picking-he acutally has one on his neck and one on a stand in front of him an plays 2 and a time. I cannot remember his name, but the next time I see him, I will reply. Perhaps someone else knows of him. He is a younger black gentleman and can really wail-You could use both hands and play guitar like a piano, essentially.
As far as the slide, I meant you could put in on one of the other fingers.
Check out some Leo Kottke stuff-learn the style and then electrify it-Who knows-maybe we will all be in line trying to get a CD of that "new sound."