Larry Lessig calls law professor Yochai Benkler "the leading intellectual of the information age." He studies the commons -- including such shareable spaces as the radio spectrum, as well as our shared bodies of knowledge and how we access and change them.
His most recent writings (such as his 2006 book The Wealth of Networks) discuss the effects of net-based information production on our lives and minds and laws. He has gained admirers far beyond the academy, so much so that when he released his book online with a Creative Commons license, it was mixed and remixed online by fans. (Texts can be found at benkler.org; and check out this web-based seminar on The Wealth of Networks.) He was awarded EFF's Pioneer Award in 2007.
He's the Berkman Professor of Entrepreneurial Legal Studies at Harvard, and faculty co-director of the Berkman Center for Internet and Society (home to many of TED's favorite people).