GNU Octave - GNU Octave is a programming language for scientific computing.
Maxima - Maxima is a fairly complete computer algebra system written in Lisp with an emphasis on symbolic computation.
Xoctave - The Affordable Matlab alternative which makes you save money. Xoctave is a powerful software that is meant to unleash the power of GNU Octave by creating a complete scientific computing environment.
Wolfram Mathematica - Mathematica has characterized the cutting edge in specialized processing—and gave the chief calculation environment to a large number of pioneers, instructors, understudies, and others around the globe.
QtOctave - QtOctave: a front-end for Octave/un Front-End para Octave
Xcos - Xcos is a graphical editor to design hybrid dynamical systems models.