Online Scientific Notebooks, Course, Visualization show and tell comics

Course, Visualization, Notebooks

We could add Mathematica, WolframAlpha, but they are not so free.

Also Geogebra (https://www.geogebra.org/) is almost there, if only its interface was not so complicated. It is a shame that this tool has not more success!

Sound banks

"Conserve the sound" http://www.conservethesound.de/  online museum for vanishing and endangered sounds. The sound of a dial tel...