XWiki is a WikiWiki clone written in Java that supports many popular features of other Wikis like the Wiki syntax, version control, attachments, security, and searching, but also many advanced features like templates, database and dynamic development using scripting languages (Velocity, Groovy, Ruby, Python, PHP, and more), an extension system and skinability, J2EE scalability, an XML/RPC remote API, statistics, RSS feeds, PDF exporting, WYSIWYG editing, an Office viewer and importer, and a lot more.
Cerb is a fast and flexible Web-based platform for business collaboration and automation. It helps you remember anything about anyone, collaborate from anywhere, deftly reply to a flood of email, automate, stay informed, capture feedback, track time, flag opportunities, manage tasks, share expert knowledge, and otherwise execute efficiently.
phlyMail is a groupware, webmailer, and PIM. It offers unlimited nested groups, unlimited POP3/IMAP profiles, quotas, an integrated address book, a calendar with multiple reminders and event repetitions, a file manager with an integrated WebDAV server, the ability to send faxes, SMS support (which lets you send SMS, get reminded of events via SMS, and get email notification via SMS), a bookmark manager, themes, and multilingual support. It uses either sendmail or SMTP to send email, and can handle MIME and SSL connections. Support for IDN (Internationalized Domain Names) is included. Through its modular design, it's easy to add completely new features as modules, which can be plugged into the system.
Pandora is a distributed system to monitor processes, performance, status, application, or operating parameters of almost any operating system. It has a decentralized management system, based on flexible user profiles, that allows the user to generate graphical reports, define alarms, and a full incident management system to operate a 24x7 monitoring team.
Ariadne is a Web Application Framework and Content Management System built with PHP. It allows you to build complex Web applications and sites with ease. It takes care of the mundane stuff like internationalization, security, user management, templating, data retrieval and storage, caching, and site management. It stores content in a structured object store that can be accessed through an extensive filesystem-like API.
Selador is a browser-based fantasy game. The game was commercial at first, but has since been released as open source by its developers. The game focuses on teamplay and communication between players. Although it is played in real-time, strategy and planning are paramount. It comes with a nice set of graphics and a pre-populated database. It can be installed on any *AMP stack.
OpenPSA is a Web application designed specifically to meet the needs of Web agencies and consultants. It aims to be a one-stop solution for the management of typical agency business processes, such as project management and time tracking, invoicing and document management, and group calendars. It also includes CRM features such as sales force automation and direct marketing, and is extendable via the builtin component framework.