Spring is a versatile 3D RTS game engine. Using extensively Lua for scripting game-specific code to make nearly every aspect of the engine customizable, from GUI, to unit AI, to pathfinding.

Hedgewars, it's a Blast! This is the funniest and most addictive game you'll ever play - hilarious fun that you can enjoy anywhere, anytime. Hedgewars is a turn based strategy game but the real buzz is from watching the devastation caused by those pesky hedgehogs with those fantastic weapons - sneaky little blighters with a bad attitude!...

Sparse, the semantic parser, provides a compiler frontend capable of parsing most of ANSI C as well as many GCC extensions, and a collection of sample compiler backends, including a static analyzer also called "sparse". Sparse provides a set of annotations designed to convey semantic information about types, such as what address space pointers point to, or what locks a function acquires or releases....

Dotclear is a blogging platform in PHP.
It has an easy to use web interface and a big French community.

pfSense is a free, open source customized distribution of FreeBSD tailored for use as a firewall and router. In addition to being a powerful, flexible firewalling and routing platform, it includes a long list of related features and a package system allowing further expandability without adding bloat and potential security vulnerabilities to the base distribution. pfSense is a popular project with more than 1 million downloads since its inception, and proven in countless installations ranging from small home networks protecting a single PC to large corporations, universities and other organizations protecting thousands of network devices. ...

Linux is a clone of the operating system Unix, written from scratch by Linus Torvalds with assistance from a loosely-knit team of hackers across the Net. It aims towards POSIX and Single UNIX Specification compliance.

NServiceBus is a powerful, yet lightweight, open source messaging framework for designing distributed .NET enterprise systems.
Entirely pluggable yet simple to use, NServiceBus gives programmers a head-start on developing robust, scalable,
and maintainable service-layers and long-running business processes....

CiviCRM helps organizations grow and sustain strong relationships over time.

CiviCRM is a web-based, open source, Constituent Relationship Management (CRM) software geared toward meeting the needs of non-profit and other civic-sector organizations.

As a non profit committed to the public good itself, CiviCRM understands that forging and growing strong relationships with constituents is about more than collecting and tracking constituent data - it is about sustaining relationships with supporters over time....

The free, open-source, Unix administrative tool lsof (for LiSt Open Files) displays information about files open to Unix processes.

Free open sourced git project and repository hosting with a twist,