CGAL - Computational Geometry Algorithms Library
List of differentiation identities - Wikipedia, the free encyclopedia
Lists of integrals - Wikipedia, the free encyclopedia
List of logarithmic identities - Wikipedia, the free encyclopedia
List of limits - Wikipedia, the free encyclopedia
List of mathematical series - Wikipedia, the free encyclopedia
List of trigonometric identities - Wikipedia, the free encyclopedia
Mathomatic - a computer algebra system
Octave - GNU project, similar to Matlab
R - GNU R - statistics/math language