Howdy again. I didn't mention this earlier 'cause of a general sense of longwindedness but here goes.
Once in a while I've tuned the octave strings a 3rd, 4th, or 5th away from their lower mates, but this requires very specific tune to tune attention. The effect is cool and worth trying. The fifths allow for a sorta power chord thing to happen, which is great for open string drones.
Fun, huh? Mooh.