Openserving
(If you have an existing blog or website, we encourage you to register and apply for an account. However, the overwhelming response to Openserving means that it could be a few weeks before we are able to reply to your request and create your account.)
Openserving extends the essence of the open source model – free software and content – to all aspects of web-based computing.
Popular existing web communities can create their own open-content, collaborative, blogging systems.
update 1/1/2008:
Openserving seems to be gone and redirects to Wikia
☍ 21.02.2007