Sorry, evidently had a URL from a previous post in the "copy" bucket--now edited for correct subject title!
If you have good off-trail skills (especially navigation skills), Wyoming's Wind Rivers is a grand place to get away from the beaten path. I'm planning two back-to-back trips, partially off-trail, this summer. A number of off-trail routes there require mountaineering skills and glacier travel skills, and you definitely wouldn't want to do those kind of trips alone. But there are many others that just require good route-finding and elementary scrambling skills. A wonderful book that will give you lots of ideas has recently been published: Nancy Pallister's "Beyond Trails in the Wind River Mountains of Wyoming." You can find a preview and purchase the book on this website: http://www.mcreynoldscpa.com/BeyondTrails
I recommend getting the accompanying CD, which has better maps than are in the book and many beautiful photos which will have you drooling! Do read the route descriptions carefully and honestly assess your skills before trying any of the routes listed.