Project Gutenberg
Project Gutenberg offers thousands of ebooks free to download
Coursera
Coursera offers free online courses from high ranked universities, such as Stanford, MIT and many others.
Udacity
Udacity offers free technichal courses from top companies, such as Google, Autodesk and nVidia.
WorldScienceU
Courses in science from the world\s top educators.
Maker Zone
Lots of projects and stories based on Arduino, Raspberry Pi, Lego Mindstorms and Matlab.
Maker Pro
Electronics and projects by the community.
Cornell Creative Machines Lab
Interesting robotics projects inspired by nature.
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