The bsd-licensed HWIOS (http://hwios.org) project was started rougly a year ago to provide an easy-to-use web-UI to the Opensimulator virtual world platform, which is quite hard to control for non-technical users. It was built from ideas and flaws that were gathered and discovered from it's php predecessor WiXTD. HWIOS is a python CMS that's built on top of frameworks like Twisted, Django, JQuery and friends. It's a rather unconventional CMS because it relies solely on XHR and websockets for data(JSON) transport; hence it doesn't use page refreshing.
It's architecture is well suitable to provide realtime collaborative text-features and notification systems in today's applications like a wiki, the forum or news apps. It uses a two-way JSON-RPC router for easy delivering of data from client-server and vice-versa.
Another thing that's interesting to implement is the html5 canvas tag, that can be used for shared whiteboards, visualisation of data structures, and more. The amount of features in HWIOS is still limited because of a lack of developers. The current focus is to finish the wiki system, refactor and comment the code and add internationalisation. Developers who are interested can check out the code from the git repository.