As a footnote to my rant on Libertarians' blindness to income inequality, I've been reading through some ideas coined geolibertarianism. The group describes itself as a fusion of Green and Libertarian ideals, which by itself makes it worthy of a read, and my initial assessment is that they pull it off pretty well (although they definitely have a Libertarian elitism -- at one point they critique Libertarians merely for having blind spots, and Greens for being counterrational).
Their main breaking point with the Big Ls is the argument that land ownership itself is a government monopoly: the system we've got today is not based on the Libertarian principle that one has a right to the fruits of one's own labor, but on a holdover from the days of monarchy -- a small group of powerful people is given sanction to extract payment from those actually putting labor into the land they "own." Someone who's born owning eight million acres and who sits back and earns a fortune their whole life from renting it out might not be entitled to that free ride! Imagine that!
This doesn't have a tremendous bearing on income inequality, but I thought I'd point it out as a note of side interest. It's certainly a step in the right direction for Libertarian thinking, and does address one of its major blind spots.