Bryan Caplan makes a good point with his and Zac Gochenour's search-theoretic critique of Henry George's tax on the value of unimproved land. It's similar to a point that Charles Hooper made in his bio of Henry George in The Concise Encyclopedia of Economics. Hooper writes:
George was right that other taxes may have stronger disincentives, but economists now recognize that the single land tax is not innocent, either. Site values are created, not intrinsic. Why else would land in Tokyo be worth so much more than land in Mississippi? A tax on the value of a site is really a tax on productive potential, which is a result of improvements to land in the area. Henry George's proposed tax on one piece of land is, in effect, based on the improvements made to the neighboring land.
And what if you are your "neighbor"? What if you buy a large expanse of land and raise the value of one portion of it by improving the surrounding land. Then you are taxed based on your improvements. This is not far-fetched. It is precisely what the Disney Corporation did in Florida. Disney bought up large amounts of land around the area where it planned to build Disney World, and then made this surrounding land more valuable by building Disney World. Had George's single tax on land been in existence, Disney might never have made the investment. So, contrary to George's reasoning, even a tax on unimproved land reduces incentives.