Contao is a content management system (CMS) for people who want a professional Internet presence that is easy to maintain. The state-of-the-art structure of the system offers a high security standard and allows you to develop search engine friendly Websites that are also accessible for people with disabilities. Furthermore, the system can be expanded flexibly and inexpensively. It features easy management of user rights, a Live Update Service, a modern CSS framework, and many integrated modules (news, calendar, forms, etc.).
Dr. Geo is an interactive geometry program that is distributed as a universal portable application. It allows one to create a geometric sketch and manipulate it according to its constraints. It is usable at home or at school, in primary or secondary education. It is simple and effective with extended features including scripting and programming.
Gimp User Filter is a work-alike to Adobe's Filter Factory. It is a generic image processing plug-in that can be used to create new filters for The GIMP without having to go through the process of learning about The GIMP's SDK. Many freely available filters that have been created for Filter Factory can also be used with this plug-in.
Jitsi (formerly SIP Communicator) is an audio/video and chat communicator that supports protocols such as SIP, XMPP/Jabber, AIM/ICQ, Windows Live, Yahoo!, Bonjour, and many other useful features. It is currently the most feature rich Internet Communicator, and is the only one to provide encrypted audio/video calls, desktop streaming and sharing, and chat on Windows, Mac OS X, and Linux with both the SIP and XMPP protocols.