Qt is a comprehensive, object-oriented development framework that enables development of high-performance, cross-platform rich-client and server-side applications. When you implement a program with Qt, you can run it on the X Window System (Unix/X11), Apple Mac OS X, and Microsoft Windows NT/9x/2000/XP by simply compiling the source code for the platform you want. Qt is the basis for the KDE desktop environment, and is also used in numerous commercial applications such as Google Earth, Skype for Linux, and Adobe Photoshop Elements.
The SeaMonkey project is a community effort to develop an all-in-one Internet application suite. It contains an Internet browser, email and newsgroup client with an included Web feed reader, HTML editor, IRC chat, and Web development tools, and is sure to appeal to advanced users, Web developers, and corporate users. It uses much of the Mozilla source code powering such successful siblings as Firefox, Thunderbird, Camino, Sunbird, and Miro.
GNUnet is a peer-to-peer framework with focus on providing security. All peer-to-peer messages in the network are confidential and authenticated. The framework provides a transport abstraction layer and can currently encapsulate the network traffic in UDP, TCP, HTTP, HTTPS, or direct 802.11 (WLAN). GNUnet supports accounting to provide contributing nodes with better service. The services built on top of the framework include anonymous file sharing and a virtual network providing IPv4-IPv6 transition via protocol translation over the P2P network.
Wt is a C++ library for developing Web applications with an API that is widget-centric and inspired by existing C++ graphical user interface APIs. To the developer, it offers abstraction of Web-specific implementation details, increasing the accessibility and portability. Under the hood, the library uses the latest techniques (HTML5, Ajax, WebSockets) to handle user events and update the Web page.
DirectFB is a thin library that provides developers with hardware graphics acceleration, input device handling and abstraction, an integrated windowing system with support for translucent windows and multiple display layers on top of the Linux framebuffer device. It is a complete hardware abstraction layer with software fallbacks for every graphics operation that is not supported by the underlying hardware.
U++ is a C++ cross-platform rapid application development suite focused on programmers' productivity without sacrificing runtime performance. Based on strictly deterministic design, it provides a viable alternative to garbage-collected platforms, even for business logic oriented problems.
Heartbeat is a full-function high-availability system for Linux and other POSIX-like OSes. It monitors services and restarts them on errors. When managing a cluster (more than 1 machine), it will also monitor the members of the cluster and begin recovery of lost services in less than a second. It runs over serial ports and UDP broadcast/multicast, as well as OpenAIS multicast. It is easily adapted to different interconnect media and protocols. When used in a cluster, it can operate using shared disks, data replication, or no data sharing. Versions starting with 2.0 are comparable to any commercial HA package, providing resource monitoring, larger clusters, and detailed dependency information.
Libzdb is a database library with thread-safe connection pooling. The library can connect transparently to multiple database systems. It has zero runtime configuration and connections are specified via a URL scheme. A modern object-oriented API is provided. Libzdb supports MySQL, PostgreSQL, SQLite, and Oracle.