The Principality of Sealand
This micronation wins a place on this list for extreme silliness. Originally built by the British in WWII, HM Fort Roughs is a 5,900 square-foot sea fortress off the coast of Suffolk. A pirate radio broadcaster named Paddy Roy Bates took over the platform in 1967 and proclaimed it his own sovereign nation: the Principality of Sealand. Though no other nation recognizes the micronation as autonomous, Bates has issued passports, postal stamps, and instituted a family monarchy. He passed away in 2012, but his son seceded him as Regent, and will continue the Sealand legacy.