This list of free internet knowledge was compiled in an /r/reddit.com thread 3 years ago.
Schools and Universities:
--LearnJava
--GA Tech Free Java Learning Materials
--Blue Pelican Java Textbook
--MIT 6.092 Intro to Programming in Java
--CalTech CS Java Track (This is just a syllabus, with assignments and labs, but you can work through it the same way the students did)
--ORACLE's Java Tutorials
--FHDA Community College Intro to Java Course
Schools and Universities:
- University of Reddit with subreddit
- MIT Lectures
- Carnegie Mellon
- Johns Hopkins
- Tufts
- Rice - Connexions
- Utah State
- Berkeley
- Berkeley Part 2
- Berkeley Part 3 (videos)
- Stanford
- Stanford Part 2 (videos)
- Harvard
- University of Sydney
- University of Virginia
- Stanford
- Yale
- Yale Part 2 (videos)
- University of Chicago
- University of New South Wales
- Open Course Ware Finder
- Open Course Ware Consortium
- University of the People
- P2P University - "Learn anything with your peers" (recommended by johndbritton via PM)
- 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.
- Wikiversity
- Youtube Edu
- 100 Best Intro Courses
- Khan Academy
- Open Culture
- TED
- Cosmo Learning
- Knol
- Academic Earth
- Free Video Lectures
- More Video Lectures
- Directory of Open Access Journals
- Learners TV
- IncrediCampus
- LectureFox
- Freelance-Teacher
- National Programme on Tech Enhanced Learning
- Study Blue
- WikiHow
- How Stuff Works
- Wonder How To
- Better Explained
- TeachMate
- Learning Schedule Tracker - Smart.fm
- Mixergy - "Where entrepreneurs teach" requires E-mail address (recommended via PM)
- Carl H Programming with corresponding subreddit
- Google Code University
- The New Boston - Step by step lessons for multiple languages (recommended by Exano and Dsch1ngh1s_Khan via PM)
- Learn about Linux
- Free Technology Academy
- University of Washington CSE
- Lynda.com
- Web Building Tutorials
- Building Websites via Academic Earth
- Opera Web Standards Curriculum
- Stack Overflow (Question Site)
- D Zone (Question Site)
- VideoCoPilot - Tutorials for Adobe After Effects (recommended by Dsch1ngh1s_Khan via PM)
- Nettuts - Web development tutorials (recommended by Malpercio via PM)
- Bloc - "Bloc makes it easy and fun to learn how to program" (recommended by scrappy D00 via PM)
- Teoria - Classical Music Theory (recommended by WhatYouGive via PM)
- Funk University
- Piano Lessons
- Music Theory - Trainear.com
- Music Theory - MusicTheory.net
- Guitar Lessons at Ultimate-Guitar
- Guitar Lessons at The Stringery
- Guitar Lessons at The Next Level Guitar
- Guitar Lessons at Justin Guitar
- Bass Lessons
- Chord Book - Chordbook.com
- Chord Book - Chorder.com
- Guitar Neck Quiz
- LiveMocha
- Languages from BBC
- FSI Language Courses
- Duolingo - "Learn language for free and translate the web" (recommended by TychePsyche via PM with associated TED Talk)
- Talk To Me In Korean - a website for lessons on speaking Korean (very highly recommended by biscuitlol via PM)
- Good Eats (alternate video source)
- Cooking Coarse (Youtube Search Summary)
- Jamie's Home Cooking Skills (recommended by pasteve via PM)
- Project Gutenburg
- Planet eBook
- The Free Library
- Google Books
- Open Book Project
- WikiBooks
- Safari Books Online (paid subscription needed)
- Using Open Edu Resources - eBook (.pdf)
- How to Think Like a Computer Scientist - eBook
- Large list of science eBooks
- Scribd
- WorldCat - Worldwide Library Catalog
- Cornell University - arXiv.org
- Cite Seer
- Scirus
- Get Cited
- Online Library - ibiblio
- Librivox - A free audio book website (recommended by city_lights and thecheese_cake via PM)
- The Assayer - "The web's largest catalog of books whose authors have made them available for free." (recommended by grbgout via PM)
- The Math Motherload
- Western Civilization
- Psychoactives
- Philosophy
- Make Magazine
- Self Improvement - 101 Linked Resources
- Custom Action Figures
- Exercise
- Yoga
- Raising Chickens
- Argument Mapping
- Investing
- Instructables
- Physics for Future Presidents
- Creative Live
- Let's Make Robots
- InfoPlease - Almanac
--LearnJava
--GA Tech Free Java Learning Materials
--Blue Pelican Java Textbook
--MIT 6.092 Intro to Programming in Java
--CalTech CS Java Track (This is just a syllabus, with assignments and labs, but you can work through it the same way the students did)
--ORACLE's Java Tutorials
--FHDA Community College Intro to Java Course