Academic Earth

Academic Earth is a site with full recordings of lectures from top universities, mostly entire courses. It holds a treasure trove of incredibly valuable, free education ranging from Introduction to Computer Science with Java (or C) to Literary Theory to Introduction to Psychology.

Vitals

It was started in 2009 to much fanfare, intended to be the "Hulu of learning." But not much has been heard about it since the beginning of 2010 and it's not clear how they intend to stay alive. TechCrunch's database doesn't show many milestones since then, and only declining traffic. And we all know what happens when traffic declines!

Preservation

There are tons of educational content on the site, and it seems that most videos have a "download" link that let you grab the video file. Even ones that don't have the link are grabbable by video rippers like Video DownloadHelper. So they're not so protected that they're impossible to automatically download.