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.
spuug is a little tool that generates the boilerplate code for GObjects. spuug can be used for "plain" GObjects, but also for more sophisticated objects such as GTK+ widgets. It tries to be a bit smart with the code in spits out. However, understanding of GObjects/GtkWidgets is recommended.
The OATH Toolkit makes it easy to build one-time password authentication systems. It contains shared libraries, commandline tools, and a PAM module. Supported technologies include the event-based HOTP algorithm (RFC4226) and the time-based TOTP algorithm (RFC6238). OATH stands for Open AuTHentication, which is the organization which specifies the algorithms. For managing secret key files, the Portable Symmetric Key Container (PSKC) format described in RFC6030 is supported.
Gcmc is a front-end language for generating G-code, SVG, and DXF for CNC mills, lathes, laser cutters, and other numerically controlled machines employing G-code, SVG, or DXF. The language is a context-free grammar created to overcome the archaic format of G-code programming, but can be used more generally for many targets. Gcmc aims to be more readable and understandable than G-code and enable programmatic designing. Gcmc makes extensive use of vector mathematics to support the 3D nature of CNC machining. It handles units as millimeters, mils (inch), degrees, and radians and performs automatic conversions where necessary.