GNU TeXmacs is a free wysiwyw (what you see is what you want) editing platform with special features for scientists. The software aims to provide a unified and user friendly framework for editing structured documents with different types of content: text, mathematics, graphics, interactive content. TeXmacs can also be used as an interface to many external systems for computer algebra, numerical analysis, and statistics. New presentation styles can be written by the user and new features can be added to the editor using Scheme.

Ch is an embeddable C/C++ interpreter for cross-platform scripting, shell programming, 2D/3D plotting, numerical computing, and embedded scripting. It is the simplest solution to numerical computing and visualization in the domain of C/C++. It supports the ISO 1990 C Standard (C90), major features in C99 (complex numbers, variable length arrays or VLAs, type generic functions, long long data type, etc), classes in C++, and extensions to the C language like nested functions, string types, etc. It can be embedded in other applications and hardware and used as a scripting language. C/C++ code is interpreted directly with no compilation to intermediate code. It supports Linux, Windows, MacOS X, Solaris, HP-UX, and FreeBSD.

Frink is a calculating tool and programming language designed to help you in the real world. It tracks units of measurement throughout all calculations and ensures that answers are correct. It converts between systems of measurement, and has a huge library of physical data. It is both a simple calculator for quick calculations and a full-fledged programming language for large tasks. It draws high-quality graphics, handles conversions between time zones, currencies, and historical values of the U.S. dollar and the British pound, translates between several languages, does date/time math, and more.

The goal of Hilbert II, which is in the tradition of Hilbert's program, is the creation of a system that enables a working mathematician to put theorems and proofs (in the formal language of predicate calculus) into it. These proofs are automatically verified by a proof checker. Because this system is not centrally administered and enables references to any location on the Internet, a world wide mathematical knowledge base could be built. It also contains information in "common mathematical language".

WIMS (WWW Interactive Mathematics Server) is a CGI Web application designed to host interactive mathematical educational activities such as exercises, computational math, and graphing tools. It features automatic score processing with strong anti-cheating mechanisms, virtual classes allowing teachers to guide/control student works, online exercise creation, animated graphics, a message board allowing inline mathematical formulas, and more. It can also be easily used for education within other disciplines.

alph implements and analyzes historical and traditional ciphers and codes, such as polyalphabetic, substitutional, and mixed employing human-reconstructable algorithms. It provides a pipe filter interface in order to encrypt and decrypt block text to achieve transparency. The program is meant to be used in conjunction with external programs that transfer data, resulting in transparent encryption or decryption of information. The program can thus be used as a mail filter, IRC filter, IM filter, and so on.

Condorcet with Dual Dropping is a ranking system for deciding single or multi-winner contests (elections) using voted preference (or approval) ballot list or pairwise tally matrix. It computes the Cloneproof Schwartz Sequential Dropping (CSSD) and Tideman's Ranked Pair (RP) results for each contest round, and selects the combined CSSD and RP outcome with the lowest overall dropping cost. There are options to compute just the CSSD, RP, or Minimum Dropping Cost outcome, various optional pair rank and winner tie-breakers, and alternative measures of dropping cost (winning votes and/or margin). It comes as a console program and CGI executable.

XiStrat (aka 'Extended Strategy') is in particular about turn-based, networked multiplayer, non-cooperative, zero-sum, abstract strategy board games (e.g., Chess, Go, Reversi variants, etc.) on 3D-visualized polyhedra and contains a server, client GUI, autoplayer engine, utilities, and documentation. Related recreational modern mathematics (single agent, cellular automata, graph/group/complexity/knot theory, discrete geometry, algebra, combinatorics, and mathematical physics) is also dealt with.