GPP is a general-purpose preprocessor with customizable syntax, suitable for a wide range of preprocessing tasks. Its independence from any programming language makes it much more versatile than cpp, while its syntax is lighter and more flexible than that of m4. The syntax is fully customizable, which makes it possible to process text files, HTML, or source code equally efficiently in a variety of languages.
SDL.NET is a set of object-oriented CLS-compliant .NET bindings for the SDL gaming library. It provides high-level access to audio, keyboard, mouse, joystick, TrueType fonts, various image formats, sound mixing, MPEG-1 movies, and 3D hardware via OpenGL and a 2D video framebuffer. It is compatible with both .NET and Mono runtimes.
Aorta is a load-balancing clustered P2P application. It executes Tasklets (which have the ability to split themselves into sub tasks that can be executed in pararell). A typical cluster contains of a LAN with 1-256 computers, each one running aorta. A Tasklet can be of any type ranging from encoding MP3s, Genomic DNA Alignment, or simply to rendering Web pages for high speed/heavily loaded Web sites. You can make functions calls to C/C++, applications like Matlab, etc.
Af-Arch is an N-tier development framework to quickly build high-quality distributed applications. It currently supports C and C# programming languages, which enables you to write client applications using them. It currently runs on GNU/Linux and Microsoft Windows, and is being used in production environments.