When I was at GR the other day, Jim put a 12-fret through the paces for me to enjoy.
After playing around in standard tuning, he paused and started turning the tuning machines and pretty soon he strummed a nice sounding chord, open D (D A D F# A D).
Like I've said before, I'm a guitar newb and was not familiar with that tuning.
Had a great, relaxed, blue-grassy sound to it, and so yesterday I put my (brother's) Norma acoustic into open D and have been messing around a bit.
I've always considered the Norma a pretty mediocre dreadnought, but I was pleasantly surprised how good it sounded in open D, plus, with the relaxed tension the high-action is not as much of an issue.
Was poking around on YouTube and found a neat little video about playing "Vestapol" in open D, plus I've been trying a bit of "She Talks to Angels" (Robinson/Robinson) which is played in open E, by capo'ing open D at the 2nd (according to what I've read today). I don't have them totally figured out yet, but I'm having a blast! (Except I broke a huge chip off my R index finger nail today, opening a drawer.

)
I'm still learning EADGBE, but I'm really excited to be experimenting with open D, it's like a whole 'nother instrument in my hands.
What fun!

-Kris
(Aforementioned "Vestapol" lesson on YouTube:
http://www.youtube.com/watch?v=yIm84L6GPmk )