Here is where I would like to collect a list of free online textbooks, books in general, ebooks, audiobooks, courses and lectures, etc. Add yours if you have a good link!
Free online books/resources:
Textbook Revolution - Probably the best known (and possibly largest) one for free textbooks; searchable
The Assayer - Discussion and links to free textbook resources
Textbooks in Mathematics - Mathematics Textbooks
FreeBooks4Doctors.com - Links to, and discussion about lots of free Medical Books
WikiBooks - Lots of free Wiki Books
The Online Books Page - Links to tons of free books (hosted at the University of Pennsylvania)
Free High School Science Texts - Science Textbooks, mostly at the high school level
FreeTechBooks.com - Free computer science books and lecture notes
Project Gutenberg - lots of free books, searchable by name (or you can list by most popular, etc.)
PubMed
195 Free Online programming books - The name says it all really
2020 OK.com - Directory of free Online books
http://www.ebooksclub.org/ - They have everything from textbooks to popular fiction.
The complete notebooks of Leonardo da Vinci - All of Leonardo's notebooks gathered into a single file.
http://www.totallyfreemath.com/ - Free math book published because they think the cost of textbooks is too high.
LibriVox - Public Domain Audiobooks
AvaxHome - Lots of ebooks, audiobooks, etc.
HarperCollins - A major book publisher has just started offering many of their books for free online
Free online university courses:
MIT OpenCourseWare - Lots of free course material for self education, provided by MIT
UC Berkely iTunes U - Lots of courses (perhaps every course?) from Berkeley University free through iTunes.
Stanford iTunes U
Open Courseware Consortium - A bunch of universities that put their course material online for free
Wikiversity - Same concept as wikipedia, but with online courses. They have assignments, homework, etc. for each course.
UC Berkley Online Classes - A Ton of online video and audio lectures from just about every course (look back at previous semesters if you don't see one) This one is really good if you want to watch all the lectures from an entire semester of courses.
(Note: Some of these added in later responses, but I am putting them all into this thread for future people viewing it)
Edited by Live Forever, 20 February 2008 - 03:15 AM.