Itunes U

Over 350,000 files are now being provided via the service, Apple said.

Over 800 universities throughout the world have active iTunes U sites, and nearly half of these institutions (including Harvard, MIT, Cambridge, Oxford, University of Melbourne and Universit de Montral) distribute their content publicly on the iTunes Store, the company added

Source: http://www.pcmag.com/article2/0,2817,2368238,00.asp