Duflo and Banerjee are the founders of the Jameel Poverty Action Lab (JPAL), behind the most interesting and fascinating new research on poverty issues in the Developing World, and are having a significant impact on international aid and development interventions.
Their courses are generally hard to get into (I can personally attest to this), and expensive. But now you can get it for free. Definitely check it out!
Further reading: Tworque/JPAL