If you play finger-style guitar, then you should get - - load any MIDI file and display it in any tuning!

Then your musician's skills come into play as you decide a tuning in which to play the music and the best way of fingering the tune. In my arrangements I try to leave open strings ringing while other notes are playing - on the banjo this was developed by Bill Keith and is is often known as 'melodic banjo'. Try Keith Hinchliffe's recordings for the same effect on the guitar. The principle works well for Celtic tunes and open tunings but you need to play them live to hear the full effects - listen to some of the mp3 files here.