Khanacademy--2400 + video tutorials on everything frm arithmetic to calculus. Site includes Finance, history, test preparation, physics and many other subjects. Everything is free. It promises to help you learn when you're ready to learn. http://www.khanacademy.org/

iTunes U--More than 800 universities have active iTunes U sites. About half of these institutions — including Stanford, Yale, MIT, Oxford, and UC Berkeley — distribute their content publicly on the iTunes Store. You will need to download and install the free iTunes software (for Mac or Windows) for easy access to these courses. Also, use iTunes software to search many educational podcasts. To learn more, check http://www.apple.com/education/itunes-u/whats-on.html. To download iTunes software, go to http://www.apple.com/itunes/download/.

MIT Open Courseware-- A wonderful attempt to make most materials for MIT classes available on the web, free of charge. Go to http://ocw.mit.edu/index.htm

See also the links on our Database page and Good Resources page