Many interesting things!

Solving the Rubik Cube – Theory – http://geometer.org/rubik/group.pdf

 

learn online – https://iversity.org/

A curated magazine – http://magazine.theascender.org/

Exercices cheat sheets – http://neilarey.com/

learn online – https://learni.st/

Scrolldown interactive page showing distances of solar system and where mankind has reached – http://www.bbc.co.uk/bbc.com/future/bespoke/20140304-how-big-is-space-interactive/index.html

well… check it out 🙂 http://madeinthefuture.co/

learn online – https://www.udacity.com/courses#!/all