Laissez-Faire city was a new country attempt in the 1990s, based in Costa Rica. Despite many flaws in the idea (some of which I document in my 2001 visit to CR), I will always have a warm spot in my heart for it, as it was the first project I had some firsthand experience with. Here is the ad they took out in The Economist in June of 1995:
You may also want to see John Kingman’s report. (John later moved to CR, and I stayed with him during my visit).