Not far from the Praterstern subway station in Vienna, you end up at the border of the Republic of Kugelmugel, a surface-minimizing micro-nation founded by Edwin Lipburger. The Republic of Kugelmugel declared independence in 1984. Its address is "2, Antifaschismusplatz" (2, Anti-Fascism Square, 2 refers to the 2nd district Leopoldstadt)
The story behind this globular nation is as follows: Edwin Lipburger wanted to build a spherical house, believing that it was the shape most in harmony with nature. He called the building "Kugelmugel", which roughly means "Ball Hill". When authorities complained that he lacked building permit and had to tear the structure down, Edwin responded by declaring the ball a nation of its own and started issuing money and stamps.
After a bit of to-and-fro, the house ended up being moved to the Vienna Prater, and Edwin ended up being moved to jail for refusing to pay Austrian taxes. (The Austrian president saw the comedy in it all and pardoned him.) Edwin continued his battle with the bureaucracy, which, to anyone even vaguely familiar with the Austrian "Amt"-culture, must be seen as a David versus Goliath battle.