Well, in New York there are four town-villages (Harrison, Scarsdale, and Mt. Kisco in Westchester and something in Albany County also, I forget) where the entire township is taken up by an incorporated Village, and the town exists mainly on paper. (I think it's considered a combined form of government.)
The only city in New York State that takes up a whole county takes up five whole counties. Which city is that again? I think it's near Lake Success or something? ;-)
:-) Andrew