What is remarkable about Khan Academy is that it was done. It was a huge effort. And it was done from scratch, out of nothing. Not in order to promote some crapware like Silverlight or Flash, but with commitment to teach poor people.

Collecting videos around the net and put it in one page is useless idea. There are plenty of really great courses from MIT, Yale, Berkeley and they were already aggregated on sites like academicearch.

And of course, no one could ever beat 6.001 from MIT ^_^ It is art. Btw, if you like to improve your education in CS courses from MIT are enough. For general education visit Yale. For everything else there is Berkeley. CS69A is a masterpiece.