If you’re an educator looking for a mind-mapping tool, check out Freemind. Freemind is an open source, free mind-mapping application that allows users to quickly build mind-maps and provides the capacity to enhance them with graphics and hyperlinks to external Web sites.
If you’re looking for a versatile and powerful open source chat client for Windows and Linux, then take a look at Pidgin. Pidgin supports multiple simultaneous chat room logins and a wide range of Instant Messaging protocols, including AIM, ICQ and MSN Instant Messenger.
Qimo4Kids (pronounced “kih-mo for kids”) is a free, open source Linux operating system for learners on the primary and intermediate levels. It presents a kid-friendly interface and incorporates open source educational applications to help students develop math, language and problem-solving skills among others.