Almafa.org is a free computing environment for scientific and engineering calculations.Almafa.org is a free computing environment for scientific and engineering calculations. It is different from Octave and Sage in a few ways: it supports physical quantities and runs entirely in the browser.
The actual code that runs is standard Javascript, which is compiled from a special extension of the language. This extension allows for convenient definition of matrices, vectors, quantities, special operators, etc. in a format inspired by Matlab.
Supports plots, FFT, linear algebra, and the number of libraries is growing.