Keen Talks provides you with a compilation of great talks, debates, and interviews that you can easily browse by subject area or by speaker.
2- Talk Timer
It has a wide variety of educational videos and lectures covering different topics. You can share talks you like via email, Facebook or Twitter.
3- Academic Earth
This is a free platform where you can access and watch videos and lectures from the best and well renowned universities such as Berkeley, Harvard, MIT, Princeton..
4- Learners TV
Learners TV offers video lectures to college students. These lectures cover a wide range of subjects.