PostgreSQL is a robust relational database system with over 25 years of active development that runs on all major operating systems. It is fully ACID compliant, and has full support for foreign keys, joins, views, triggers, and stored procedures (in multiple languages). It includes most SQL92 and SQL99 data types, including INTEGER, NUMERIC, BOOLEAN, CHAR, VARCHAR, DATE, INTERVAL, and TIMESTAMP. It also supports storage of binary large objects, including pictures, sounds, or video. It has native programming interfaces for C/C++, Java, .Net, Perl, Python, Ruby, Tcl, and ODBC, among others, and exceptional documentation.
Snort is a network intrusion detection and prevention system. It is the most widely deployed technology of its kind in the world. It performs detection using a variety of methods including rules-based detection, anomaly detection, and heuristic analysis of network traffic. Its rules language is open source and available to the public as well.
white_dune is a graphical VRML97/X3DV editor, simple NURBS/Superformula 3D modeller, animation tool, and VRML97/X3DV commandline compiler in development. VRML97 (Virtual Reality Modeling Language) is the ISO standard for displaying 3D data over the Web via browser plugins ("HTML for realtime 3D"). X3DV is the direct successor of VRML97. VRML97 and X3DV have support for animation, real-time interaction, and multimedia (images, movies, and sounds). white_dune can read, create, and display VRML97/X3DV files and let the user change the scenegraph/fields. It also has support for stereoscopic view via "quadbuffer"-capable stereo visuals, and support for 3D input devices like a joystick, spaceball, or magnetic tracker.
GKrellM is a GTK-based stacked monitor program that charts SMP CPUs, disks, load, active net interfaces, and internet connections. There are also builtin monitors for memory and swap, file systems with mount/umount feature, mailbox checking including POP3 and IMAP, clock/calendar, laptop battery, sensors (temperatures, voltages, and fans), and uptime. It has LEDs for the net monitors and an on/off button and online timer for PPP. There is a GUI popup for configuration, plugin extensions can be installed, and many themes are available. It also features a client/server monitoring capability.
KDevelop is an integrated development environment which makes the creation and development of applications an easy task even for beginners. Highlights of the current release are: an application wizard for easy creation of KDE 4, Qt4, GNOME, and terminal C/C++ projects, full project management, a syntax-highlighting editor, code completion, an integrated dialog editor for the Qt/KDE GUI libraries, an internal debugger, a full-featured class browser with class tools, CVS and SVN support, an integrated HTML-based help system offering manuals and class-references, and extensive search mechanisms to browse sources and documentation.
PHP Content Management System (phpCMS) makes it possible to need only one template for your whole Web site. It allows you to provide dynamic menus with unlimited levels, and use templates and sub-templates without a database. It is search engine-friendly and proxy-friendly, as the pages it generates can not be distinguished from static HTML pages. PHP code can be added to any template and content file with an optional module. It supports the caching of parsed pages and gzip compression.
Hiawatha is a secure and advanced Web server for Unix. It has been written with security as its main goal. It features advanced access control, prevention of SQL injection and cross-site scripting, banning of clients who try such exploits, the ability to run CGIs under any UID/GID you want, and many other features. These features make Hiawatha an interesting Web server for those who need more security than what the other available Web servers are offering. Hiawatha is also fast and easy to configure.
gnokii is a multisystem tool suite for mobile phones. It provides a library to communicate with a phone hiding the communication protocol. The library handles SMS, phonebook, calendar, phone calls, and other mobile phone capabilities. It supports Nokia-FBUS mobiles, AT-capable phones (most of the mobiles), as well as Symbian-based phones.
Freeciv is a multiuser reimplementation for Unix/X of the famous Microprose game of Civilization. By default, the game is an improved Civ II, but this can be customized; modpacks for near-100% compatibility with Civ I and Civ II are included. Multiuser gameplay is real-time: in each turn, all human players move concurrently. The game is designed to remain fairly playable even on poor network connections. Freeciv can also be played on standalone machines, and its AI players are a good challenge for beginners. The source code comes with the server, two X clients, and non-X clients for MS Windows and Amiga. Freeciv is released under the GNU General Public License. It is maintained by an international team of coders and enthusiasts, and is easily one of the most fun and addictive network games out there.