David Harvey has been teaching Marx’s Capital for 30 years (Capital, written in 1867 by Karl Marx, is an in-depth analysis of capitalism as an economic system). You can watch the entire course Reading Marx’s Capital (13 lectures) at his website. While looking over the site I also found LibriVoz, a website that has a number of audio books that you can download for free!
Recently, Harvey has written on the U.S. stimulus package and the unlikelihood that the U.S. will remain a global hegomon in the future.
Anthropology in the Global Age 