David Gilmour used a special tuning for the rhythm guitar in the song Comfortably Numb. It was a regular EADGBE, but the lowest two strings were two octaves higher, and the middle two were one octave ...
I like playing compositions in various tunings, and retune the guitar frequently. I only have one guitar, so that leads to two problems: Strings tend to break (much) faster when tuned up, e.g. D to ...