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.
CLAM is a multiplatform software framework for research and application development for the Audio and Music domains. It offers a conceptual model for building systems as well as tools for the analysis, synthesis, and transformation of audio signals using high level representation (notes, spectral peaks, etc.). It also provides multiplatform system abstraction and tools for audio and MIDI file handling, device handling, GUI and XML support, and more. It has proper Linux audio architecture integration (Ladspa, Alsa, OSC, Jack, VST, etc.) and rapid graphical prototyping both for the processing core and the user interface (Qt designer integration).
COID is an object-oriented networking library with a tool that automatically generates a lightweight communication layer directly from a C++ class declaration. The coidgen tool automatically extracts designated classes and methods from specified header files and generates a corresponding client class and host dispatcher. The server library manages networked and local connections and provides various services to running objects. The communication layer establishes either remote connection through TCP or direct (vtable) connection between the client and the server (if they reside in the same process).
ClearParse is a flexible engine that can be used for any parsing task including interpreting or compiling programming languages, analyzing or converting data files, processing command line parameters and user input, implementing markup languages and scripts, natural language processing (NLP), and more.
Coin is an implementation of Open Inventor. Open Inventor is the de facto standard API for retained-mode 3D graphics programming. Open Inventor has a highly extensible design, and has been designed to allow for rapid development of highly interactive 3D graphics applications in the fields of CAD, engineering, scientific computing, simulation, VRML, and visualization.
Cymbeline is an Python application server framework that includes functionality such as database and arbitrary object pooling, Web servers (including SSL), a persistent object repository, and a text console. It was originally designed as an administrative shell for an embedded system, but has since morphed into a more general purpose, run anywhere toolkit.
Firebolt is a network protocol oriented library. It's not another socket library; it offers higher level services to the developer. You can structure your protocol in the form of states and the transitions between those states with the use of your custom events. Thus you no longer need to worry about what data you just received from a socket and whether or not those data are expected in the current state of your network code, since that sort of validation is all performed by Firebolt.