A list of 875 free online courses from "leading universities". (Most are on iTunes)
http://www.openculture.com/freeonlinecourses

A list of 1000 MOOCs (many offer a certificate of completion), sorted by start date
http://www.openculture.com/free_certificate_courses

A list of free language lessons, sorted by language
http://www.openculture.com/freelanguagelessons

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