OMNeT++ is a C++-based object-oriented Discrete Event Simulation framework, primarily targeted at the simulation of communication networks and other parallel/distributed systems. It includes a graphical network editor, a network topology description language, a rich simulation class library, multiple execution environments (both GUI and command line), a result plotting tool, detailed documentation, many sample simulations, and much more.
OpenACS (Open Architecture Community System) is a mature toolkit for building scalable, community-oriented Web applications. Significant functionality is built-in, including user management, user group management, permissions, discussion forums, FAQ management, e-commerce, file storage, content management, and more. OpenACS is the foundation for many products and Web sites, including the .LRN e-learning platform.
OpenVerse is similar to other graphical chat systems like Excite Chat and Microsoft Chat, with the main differences being that OpenVerse is open source software, has no advertisements, and also runs on a variety of systems including Windows, Unix, Macintosh, and just about anything else for which you can find a copy of TCL/TK.
pkgusage lists all the packages you have installed on your system, along with a number telling you how many days ago you last accessed any of the files in the package. This could be useful for cleaning out your hard drive. Pkgusage works with RPMs and Debian packages, and is written to be easily portable to other package managers as well.
Qddb is powerful database creation software. Using Qddb, you can quickly and easily create database applications. nxqddb allows you to create a complete database application in less than five minutes, and Hx lets you manage database information over the web through a CGI interface. Larger applications can also be developed using Fx, a powerful TCL/Tk toolkit.
IRRToolSet is a set of policy analysis tools, written in C++. It's designed to run under UNIX, using Tcl/Tk for graphics. There are tools for generating router configuration files, displaying and checking routes, generating aggregations of networks, etc. This project was formerly known as the Routing Arbiter ToolSet (RAToolset), and was maintained by ISI.