"Dear Friend, all theory is gray, but the golden tree of life springs ever green." - Goethe

Pure and Applied Mathematics

Theoretical Physics

Perimeter Institute, An Introductory course by Nima Arkani-Hamed, Basic series of courses by Lenny Susskind (parts  1, 2, 3, 4, 5, 6, 7, 8, 9, 10).
Conference on computing scattering amplitudes and reformulating Quantum Field Theory: Harmony of Scattering Amplitudes Conference

P2P Economies, Open Manufacturing and Government

Psychology and Neuroscience

Neuroscience papers by Karl Friston. An intro course to Neural Computation.

Literature, Philosophy

Meditation, Mythology and Spiritual Philosophy

A philosophical intro to Zen and related traditions: Way of Zen, by Alen Watts, A scientific introduction to Mindfulness

Classical music

Performances by pianist Valentina Lisitsa, A Basic intro to playing the piano
Vi Hart explores Math and Music (papers 1, 2),

Sports, Exercise, Running

Quick summary talk about running: Are we born to run?

Cooking