Rings and Computer algebra software, part of OpenXM.
A GPL CAS based on DOE-MACSYMA. A GPL project.
Software for solving algebraic equations: GB computes Groebner bases and FGB solves polynomial systems.
A new software system devoted to supporting research in algebraic geometry and commutative algebra.
Abstract for Stanly Steinberg's article in "Comparative CAS Reviews and Philosophy", suggesting 6 ways in which computer algebra systems could be improved.
Mathscribe is free dynamic graphing and modeling software for use in algebra classes. Lesson plans for linears and quadratics are included.
A collection of routines, written in C, for computing in the representation theory of classical and symmetric groups, and related areas. Public domain.
A special-purpose system for computations in Commutative Algebra.
Computer algebra system that does arithmetic of arbitrarily long integers and fractions, symbolic calculations, graphics, and other numerical calculations. Free download. Documentation.
By Robert H. Lewis and Michael Wester. Presented as a poster to the 1999 ISSAC Conference.