eGyankosh, a national digital repository of open and distance learning resources developed by Indira Gandhi National Open University (IGNOU) had earlier been taken off due to copyright issues (as was informed by the site itself!). It has recently been relaunched.
eGyankosh is an invaluable resource for higher education enthusiasts since IGNOU is known for maintaining high standards in its content. The course materials and videos related to all the courses run by IGNOU are available on eGyankosh. One may access this huge repository just by registering.
Log on to eGyankosh at http://egyankosh.ac.in/