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.
Calligra is an integrated suite of applications that cover office, creative, and management needs. It offers applications on both desktop computers and mobile platforms like tablets and smartphones. OpenDocument Format (ODF) is used, making it compatible with OpenOffice.org, LibreOffice, and Microsoft Office. Calligra Suite contains the following applications: Calligra Words (word processor), Sheets (spreadsheets), Stage (presentations), Flow (diagrams and flowcharts), Kexi (visual database creator), Braindump (note taking), Plan (project management), Krita (drawing), and Karbon (vector graphics).
The Open Real-Time Ethernet (ORTE) is an implementation of the Real-Time Publish-Subscribe (RTPS) communication protocol. RTPS is a new application layer protocol targeted to real-time communication areas, and is built on the top of standard UDP stack. Since there are many TCP/IP stack implementations under many operating systems, and RTPS does not have any other special hardware or software requirements, it should be easily ported to many target platforms. Because it uses only UDP, it retains control of timing and reliability.
Forban is a P2P file sharing application for link-local and local area networks. Forban works independently from the Internet and uses only the local area capabilities to announce, discover, search, or share files. Forban relies on HTTP and is opportunistic, meaning that it replicates any files of interest seen in its proximity. The Forban protocols are minimalistic to ease the production of other implementations.
Marble is a Virtual Globe and World Atlas that you can use to learn more about Earth: you can pan and zoom around, and you can look up places and roads. A mouse click on a place label will provide the respective Wikipedia article. It's also possible to measure distances between locations or watch the current cloud cover. Marble offers different thematic maps: a classroom-style topographic map, a satellite view, street map, earth at night, and temperature and precipitation maps. All maps include a custom map key, so it can also be used as an educational tool for use in classrooms. For educational purposes, you can also change the date and time and watch how the starry sky and the twilight zone on the map change. Marble also features multiple projections: choose between a flat map ("Plate carré"), Mercator, or the globe.
KTorrent is a BitTorrent application that allows you to download and share files using the BitTorrent protocol. Key features include queuing of torrents, global and per-torrent speed limits, previewing of certain file types, importing of partially or fully downloaded files, file prioritization for multi-file torrents, selective downloading for multi-file torrents, kick/ban peers with an additional IP Filter dialog for list/edit purposes, UDP tracker support, support for private trackers and torrents, support for µTorrent's peer exchange, support for protocol encryption (compatible with Azureus), support for creating tracker-less torrents, support for distributed hash tables (DHT), support for UPnP to automatically forward ports on a LAN with dynamic assigned hosts, support for webseeds, scripting support via Kross, and interprocess control via DBus interface.
Libgta implements the Generic Tagged Arrays (GTA) file format. GTAs can store any kind of data in multidimensional arrays, optionally with simple tags to store rich metadata. GTAs are streamable and support mupltiple compression methods. Uncompressed GTAs allow easy out-of-core data access for very large arrays.