In southern US, from metro areas of Nashville, Atlanta, Birmingham, and rocky top Knoxville, I think Lookout Mountain GC offers interesting national/non-resident membership.
Was always enticed by Mountain Lake as well when they had a push 3 or 4 years ago, but that was a bit too far for me, and required (or maybe still requires) stay at Colony. The course is very very good. Did I say the course is a blast to play.
The problem is as Tiger states, you have to find one that you will use unless you don't mind paying and not playing. Having to fly or travel most of the day doesn't work for me.