BlueJ is an interactive Java development environment. It provides a unique user interface that presents a graphical display of the application classes and their relationships, and it lets users interactively create objects of any class. Once objects have been created, users can interact with them directly. This interaction mechanism allows for much greater testing and experimentation than in conventional environments. BlueJ is suited for teaching and learning OO and Java.
Drupal is a modular content management system, forum, blogging and community engine. It is database driven and can be used with MySQL, MySQLi, PostgreSQL, and SQLite. Its features include (but are not limited to) discussion forums, Web-based administration, theme support, a submission queue, content rating, content versioning, taxonomy support, user management with a fine-grained permission system based on user roles (groups), error logging, support for content syndication, locale support, and much more. It is considered to be an excellent platform for developers due to its clean code and extensibility, and it can also be used as a Web application framework.
Geeklog is the weblog software that concentrates on performance, privacy, and security. It features Web-based administration, surveys (polls), user-customizable boxes, a friendly administration GUI with a topic manager, an option to edit or delete stories, an option to delete comments, a search engine, backend/headlines generation (RSS/Atom format), calendaring, and much more.
HickUP is a small multi-platform system for managing applications for a user or project environment. The user can, through a GUI or command line tool, choose which applications and versions they want to use. The project manager can specify allowed applications and versions of these the project members can select. The user can then select one of multiple environments to use at login or within a specific shell.
KBiff is a KDE "biff" or new mail notification utility. It is highly configurable but very easy to use and setup. It supports session managment (it "remembers" the last state it was in before you logged off) and can be docked into the panel. It has support for mbox (Unix-style), maildir (qmail-style), mh, POP3, IMAP4, and NNTP mailboxes.
OBM is a groupware, email, LDAP, Windows PDC, CRM, and project management application. It is mainly used as a mail server, as an LDAP directory, as a Windows PDC, as a contact and customer database, as a project management tool, or as any combination of these functions. It supports internationalization and themes.
The GNU Gatekeeper is a free H.323 gatekeeper based on the OpenH323 project. You can use it to manage a Voice-over-IP network and let endpoints (e.g., Netmeeting) communicate through symbolic names. It also has an external interface for billing and other applications. It runs on a number of Unix versions (including Linux and Solaris) and Windows.
RT is an industrial-grade trouble ticketing system. It lets a group of people intelligently and efficiently manage requests submitted by a community of users. RT is used by systems administrators, customer support staffs, NOCs, developers, and even marketing departments to track issues, outages, bugs, requests, and all kinds of other things at thousands of sites around the world.