The Anarchist U is a volunteer-run collective which organizes a variety of courses on arts and sciences. Most courses run for ten weeks, and meet once a week; there are no admission fees. The Anarchist U follows the tradition of free schools in that it is open, non-hierarchic and questions the roles of teachers and students.
[Ed: First we had open source news (news-blogs), which is currently a half-dead zombie media monstrosity, then we had open source law, which works rather better. Now, we have open source education.]