1. Public Libraries
One of the most invaluable resources for a self-learner is your local public library. Not only can you find (or order) almost any book, DVD or CD that you can imagine, you can access libraries' growing collections of online and digital resources. And the best part? There's always a librarian there to answer your questions. Visit this website to find your closest public library.
The OpenCourseWare (OCW) project brings course materials from major universities directly to you - for free. Visit the consortium website above to get free online syllabi, assignments and even audio and video downloads from schools such as the Massachusetts Institute of Technology (MIT), Johns Hopkins University and Tufts University.
3. Open Learning Initiative
The Open Learning Initiative (OLI) is similar to OCW, but it provides even more material. Whereas as OCW courses can range from just a syllabus to the full course content, all OLI courses provide a set of interactive materials and lessons. Participating OLI institutions include Carnegie Mellon University and Harvard University.
Learner.org is a project by Annenberg Media, a group dedicated to supporting education through new technology. In addition to curriculum support for teachers, Learner.org offers college- and adult-level educational content on the arts, foreign language, literature, math, science and history.
There's a wealth of information available through the Public Broadcasting Station (PBS), and you can get it all for free online. Science buffs won't want to miss episodes of NOVA, and people who are passionate about politics and current events are sure to like Frontline and Newshour. Or you can surprise yourself with the curious facts on Need to Know.
Academic Earth is another great source for educational video. The site compiles free online video courses and lectures from institutions like the University of California - Berkeley, Yale University, the Massachusetts Institute of Technology and Stanford University.
Podcasts have opened up a whole new world of audio entertainment - and education. Not only can you get your favorite radio shows right on your computer or MP3 player, you can also find lectures and informational content from sources as diverse as CNN Student News and Princeton University. Check out the link above for a feed of popular educational podcasts, or download iTunes and surf the podcast directory by subject or school.
8. MIT World
The Massachusetts Institute of Technology hosts public lectures and events on topics ranging from innovations in green building technology to promoting creativity in society. Almost all of these events are recorded and offered for free on the MIT World website, which contains more than 700 videos.
A self-described 'digital library,' the Internet Archive is a nonprofit organization that collects and archives video, audio, texts and even old websites. All content is provided online for free.
10. Big Think
Big Think endeavors to provide free, open access to opinions and ideas from some of the top thinkers and experts around the world. Watch videos on feminism by the co-founder of Feministing.com, ethics by a professor in the Harvard School of Law or the psychology of spite by a psych professor at Yale University.