Variety of political movements inspired by the work of Henry George:
"Georgism is a philosophy and economic ideology that holds that everyone owns what they create, but that everything found in nature, most importantly land, belongs equally to all of humanity. The Georgist philosophy is usually associated with the idea of a single tax on the value of land. Georgists argue that a tax on land value is efficient, fair andequitable, and will generate sufficient revenue so that other taxes, which are less fair and efficient, can be reduced or eliminated." (http://en.wikipedia.org/wiki/Georgism)
"Georgists tend to believe that all humanity rightfully owns all land in common and that individuals should pay rent to the rest of society for taking sole or exclusive use of that land. People in this movement are often referred to as "single taxers," since they believe that the only legitimate tax is land rent. However, they do typically believe that private property can be created by applying labor to natural resources." 
What kind of political philosophy is Georgism ?
"One might say that George’s philosophy mixes capitalism and socialism, but it is more accurate to say that it is a distinctive philosophy that is neither capitalist nor socialist.
The central principles of capitalism in its purest form are
1) free exchange of goods in an unregulated market;
2) limited taxes to pay for limited government, and
3) private ownership of property.
The central principles of socialism are
1) government control or regulation of the market;
2) high taxes to pay for expanded government services; and
3) government ownership of major industries (particularly large industries that are prone to monopoly control).
The central principles of Georgism are
1) free exchange of goods in markets, with limited regulation of commerce;
2) no taxes on labor; high taxes on certain kinds of property;
3) private ownership of property, but fully offset by taxes that virtually eliminate unearned wealth.
Georgists agree with socialists that capitalism has failed to reconcile fairness with efficiency. Whereas capitalist policies increase national income, they also cause extreme inequality.
Georgists agree with capitalists that socialism is inefficient because government monopolies are rarely any better than private monopolies. Most policies to help the poor by equalizing incomes have the negative side effect of reducing the productive power of the economy. That is why China and Russia shifted from socialism to capitalism in recent decades.
Georgists believe it is possible to unite fairness and efficiency by taxing away the rewards of privilege so that people can earn money only by being productive. Since much of the power of modern corporations derives from those privileges, proper taxes could reduce that power." (http://povertythinkagain.com/controversies/a-word-from-the-sponsor-of-the-film-the-end-of-poverty-georgism-capitalism-and-socialism/)
- Resources for high school teachers and home schoolers: http://www.landandfreedom.org/
- The Henry George Institute: http://www.henrygeorge.org offers free online courses
- Henry George Foundation: http://www.henrygeorgefoundation.org/
- The Council of Georgist Organizations (CGO): http://www.progress.org/cgo
- The Wealth and Want website: http://www.wealthandwant.com/index.htm
Recommended by Kevin Carson of mutualist.org
- Debbie Clark : Her site includes an extended debate over Georgism with libertarian George Smith.
- The Geonomy Society: Forum on Geonomics
- Michael Hudson : Radical economist who has proposed taxes on land value and resource extraction as radical geoist response to neoliberalism in Russia and China.
- Saving Communities : Dan Sullivan's site. Lots of stuff on how geoist taxation can be used to promote progressive ends (especially eliminating urban sprawl, factory farming, etc.) within a free market framework, and on geoist taxation as an alternative to the regulatory state.
- Robert Schalkenbach Foundation : Sells lots of classical Georgist literature.
- School of Cooperative Individualism :
Ralph Borsodi's and Mildred Loomis' organization.
- Dan Sullivan's main page.