GroupOffice is a groupware suite that takes your office online, implementing online collaboration and CRM. It allows you to share projects, calendars, files and email online with co-workers and clients. It is easy to use and fully customizable. It also features synchronization with PDAs and Outlook.
Quassel IRC is a modern, cross-platform, distributed IRC client, meaning that one or more clients can attach to and detach from a central core, much like the popular combination of screen and a text-based IRC client, but graphical. In addition to this unique feature, it aims to be a comfortable chatting program.
Kune is a distributed social network focused on collaboration rather than just on communication. It focuses on online real-time collaborative editing (Wave-based), decentralized social networking (federation), and Web publishing, while focusing on workgroups rather than just on individuals. It aims to create online spaces for collaborative work where organizations and individuals can build projects online, coordinate common agendas, set up virtual meetings, publish on the Web, and join organizations with similar interests. It has a special focus on Free Culture and social movements needs.