The Cayman islands is not a sovereign state, and is a British Overseas Territory, but it is interesting.
The Cayman Islands consists of 3 islands. The region was previously a British colony and part of the Colony of Jamaica, and split as a separate crown colony in 1962. The country has no income, capital gains, or wealth tax, making it a popular tax haven.
THe Cayman Islands has a population of 56,000 and a total area of 264 sq km.