AcademicEarth

AcademicEarth is similar to the previously mentioned YouTube EDU in that it organizes videos of college lectures.  But the similarities stop there.  AE hosts only six institutions (Berkely, Harvard, MIT, Princeton, Stanford, and Yale).  It places an emphasis on lecturers and lecture topics, instead of institution.  It's easy to find lectures on a topic of choice or lectures by your favorite lecturer.  Furthermore, AE provides entire courses, not simply stand-alone lectures.  My favorite course, so far, is The American Novel Since 1945 by Yale's Amy Hungerford.  The course page even lets me access the class syllabus and final exam.  

YouTube EDU

YouTube EDU is a section of YouTube that organizes YouTube's university-sponsored channels.  Each of the channels is basically a pool of lecture videos from each particular university.  Most of the universities provide less than 100 videos, but some provide close to 1000.  My main complaint is that I can't find a way to sort the EDU videos by topic.