schools and universities:
other general sites:
openstudy - this site is highly recommended. the ceo is a fellow redditor and all around nice guy. openstudy is partnered with such institutions as mit opencourseware and yale open course, and includes 80,000 users from 1600 schools. for more info, check out this techcrunch.com article. (recommended via pm)
mixergy - "where entrepreneurs teach" requires e-mail address (recommended by andrewwarner via pm)
ebooks/online books/academic journals:
the more you know, the more you realize you don't know.
i will continue and add/edit/refine this list as my time permits. please send me a message if you spot a broken link, have general grievance with some sort of error, or have a good link we can add.
thank you everyone!
edit: it looks like this thread has been archived, so if anyone has any more suggestions please pm me. i plan to work on this list and add annotations for each link and maybe do some better organizing. when that is done i will post it again to try to get all the new links that have sprung up over the last year and to allow comments to be made again.