Step is an interactive physical simulator. It works like this: you place some bodies on the scene, add some forces, such as gravity or springs, then click "Simulate" and Step shows you how your scene will evolve according to the laws of physics. You can change every property of bodies and forces in your experiment (even during simulation) and see how this will change evolution of the experiment. With Step you can not only learn but feel how physics works!...

Mxx_ru (Make++ on Ruby) is a cross-platform build tool. It's intended for C/C++ languages in general, but it's easy to extend for handling other languages. It uses a template based approach for describing build process.

QTerm is a BBS client for Linux and Windows. It supports Telnet and SSH 1/2 protocols. It also supports zmodem, URL detect, mouse action.

An advanced C++/CLI wrapper for the OGRE 3D rendering engine, that integrates the native Ogre engine into the .NET framework seamlessly.

graph-tool is a python module to help with statistical analysis of graphs.

Its feature set includes support for both directed and undirected graphs with arbitrary vertex and edge properties, edge/vertex filtering, correlated random graph generation and community detection....

Gengetopt is a tool to generate C code to parse getopt styled command line
arguments.
It's similar or even more powerful than the well known libpopt but does not
add any run or compile time dependencies to your projects. Moreover
reading/writing the options from/to config files is also supported....

The C runtime library for the AVR family of microcontrollers. For use with GNU toolset (Binutils, GCC, GDB, etc.)

The Player Project: Player is a networked interface to robots and sensors. Stage and Gazebo are Player-friendly multiple-robot simulators. The software aims for POSIX compliance and runs on most UNIX-like OS's. Some parts also work on Windows.

Distributed peer to peer file system.,

iNFekt is all about viewing and working with NFO files.

iNFekt for Windows: A text viewer application that has been carefully designed around its main task: viewing and presenting NFO files. It comes with three different view modes (Rendered, Classic and Text Only), export functionality and lots of options! All Windows versions starting with Windows XP are supported. iNFekt works very well with Windows 7, 8 and is available in a native 64 bit version....