Thanks for link, an interesting pot-pourri from the best American Universities.
I usually delve straight into a particular university and my favourite is MIT.
Academic Earth lists 23 courses from MIT, as a contrast if you access the MIT site you will find more than 1900 courses available.
http://ocw.mit.edu/OcwWeb/web/home/home/index.htm
The other universities are similarly fruitful but for me MIT is tops allowing download of material to the hard disk for convenient off line study.
Very interesting .Thank you for the links .
You can consult this site too ....
http://www.digital-librarian.com/audio.html
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