Check out this article in the New York Post. This couple, with their two cats, lives in a 175 square foot apartment in Manhattan. Can you imagine? The article is really interesting, especially where they describe their habits which allow them to live so small. While I wouldn't be able to live in it, it's interesting to think about getting rid of the excess stuff I don't really need.
In any event, that 175 square feet of air cost $150,000.