Mathomatic is a portable, general-purpose computer algebra system (CAS) that can solve, differentiate, simplify, combine, and compare algebraic equations, perform standard, complex number, modular, and polynomial arithmetic, etc. It does some calculus and is very easy to compile/install, learn, and use. The symbolic math application with a simple command-line interface is designed to be a colorful algebra calculator that is reliable, responsive, and convenient to use. The symbolic math library is lightweight and easy to include in other software, due to being written entirely in C with no additional dependencies.
The HOTP Toolkit package contains tools that are useful when deploying the one-time password HOTP technology. It contains a shared library, a command-line tool to generate and validate one-time passwords, and a PAM module (pam_hotp) to make system login or SSH use HOTP one-time passwords for authentication.
HickUP is a small multi-platform system for managing applications for a user or project environment. The user can, through a GUI or command line tool, choose which applications and versions they want to use. The project manager can specify allowed applications and versions of these the project members can select. The user can then select one of multiple environments to use at login or within a specific shell.
libjson is a JSON parser and printer that is fully compliant with the JSON spec. The parser is efficient and interruptible with a simple and flexible API. It also optionally supports extensions like C-style comments or Python/YAML style comments, and for security allows the user to set a limit on the number of nested structures and the parse buffer. The library plugs easily into any model since it doesn't include any object model, and plugs easily in any project's memory management since the memory functions can be redefined.
InteLib is a library of C++ classes that lets you do Lisp/Scheme programming within your C++ programs, even without any additional preprocessing, without all those calling conventions. You can write code that is accepted by a C++ compiler while thinking in a "Lisp/Scheme mode", and the code you write will look much like Lisp/Scheme code, although it will be pure C++.
ff3sudoku is an add-on that features an engine for playing Sudoku puzzles. It can generate random puzzles, but it also detects and imports Sudokus from several Web sites, including websudoku.com, sudokupuzz.com, sudoku.com.au, and others. There is also a stand-alone version working in Firefox 3+ and GoogleChrome.