beaTunes is an iTunes companion app capable of automatically analyzing your music collection to help you build better playlists. It analyzes BPM (beats per minute), silence at the beginning or end of a song, and the color (based on frequency spectrum) of a given song. Some of the data is stored through iTunes, and some is stored by beaTunes itself. beaTunes can suggest albums that would complement your music collection, display music charts, and help you find and fix errors in your song meta data, like typos and wrong genres. It also allows you to blog about selected songs or playlists.
GTK, which stands for the Gimp ToolKit, is a library for creating graphical user interfaces. It is designed to be small and efficient, but still flexible enough to allow the programmer freedom in the interfaces created. GTK provides some unique features over standard widget libraries.
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.
NetPlug is an extensible multi-connections, multi-protocol, network client program, written in pure Tcl/Tk. Includes a complete Irc client plug in that you should love if you like IrcII 'classic' look & feel (plus customizable style/colors scheme, sound,... Now includes full DCC support (with GUI), ircII like aliases and improved scripting (Tcl!), keywords (your nick...) highlighting, and more