I read two articles on a similar theme this morning. Firstly there was Scott Adams' post Startup Country, about creating a small, elite, light-weight country inside another country and using it to bootstrap the economy of the larger country. Secondly I read The Politically Incorrect Guide to Ending Poverty, published by The Atlantic. This article actually talks about Paul Romer's ideas on "Charter Cities" - a city governed by it's own charter, rather than national laws. According to The Atlantic, this idea goes back to the 12th century with Heny the Lion and the idea of Imperial Free Cities.

If I squint, I can maybe see this happening. Maybe it will be more along the lines of a Burbclave - a franchised nation nestled within a gated community (as envisaged by Neal Stephenson). Of course, by the time all this happens we'll be old and decrepit, so I think they'll be more like Grayclaves. We'll all be trading bio-engineered medicines with the Grayclave next door.