Anyone else checked out the new Martin D-7 and HD-7 models? They're seven-string hybrids, essentially a regular six-string D with an extra octave-tuned G string, like on a 12-string. Roger McGuinn cooked up the idea as a custom order and Martin decided to put it in production. (Blurb from Martin's website HERE.) The D-7 is essentially a modified D-28 while the HD-7 is a modified D-41.

I tried out an HD-7 today and will admit to being quite impressed. It has just enough "jangle" to be interesting without sounding too much like a 12-string. I use a lot of three-finger banjo technigue in my guitar fingerpicking and the octave G string really jumps out.
   
No, I don't have the money to buy the real thing, but I like the idea enough that I'm seriously considering finding a suitable inexpensive used six-string and doing a modification on it.