The single tax concept, taxing land based on its value in "best use", rather than the structures on it, has been used to good effect in Australia and locally in Pittsburgh and Harrisburg.  The tax creates strong incentives for "in-fill" in urban environments, and has generated enough revenue to meet government needs.  But the tax is not based simply on land--it is based on the best use of the land, as measured by neighborhood characteristics.  Obviously, the structures on the land generate the revenue that pays the taxes.

Fred V. Carstensen