Swaminathan S. Anklesaria Aiyar, who writes articles for the Economic Times and The Times of India under the name "Swaminomics" (which is just a great name), has an interesting suggestion. He calls it community-led land acquisition. He means it to be applied to India, which has its own set of land acquisition problems, but it would work for our eminent domain ( Kelo v. City of New London (04-0108)) problem as well.
Here is the gist of his proposal as it applies to us: Governments should negotiate acquisition proposals with landowners, and then let the landowners vote on the deal. If a large majority--it could be two-thirds or three-quarters--vote in favour of selling, this should be binding on the minority.
The biggest advantage of this rule is that it prevents under-valuation of the property. The Constitution states "nor shall private property be taken for public use, without just compensation." Right now, the government decides what is just compensation, and then the government pays the price. Clearly there is vast potential for injustice there, and when you look at the history of eminent domain acquisitions, you will find plenty of charges of unjust forced sales. But by ensuring that a supermajority of landowners agrees that the price is "just compensation", that will ensure that the price really is fair.
UPDATE 3/1: Marvin writes in to point me to an article published in the Utah Daily Herald. Seems that the Utah Legislature had completely revoked the power of eminent domain. They have now replaced it with a scheme very much like the Swami describes above.