b2evolution
b2evolution is an advanced weblog tool, i-e software allowing you to run your own blogs, newsfeeds or even photo stream.
b2evolution is a medium scale CMS centered around the Blog concept, fully featured with multiple blogs, content/presentation separation, full user management, full internationalization (i18n), workflow management… and extending towards features normally provided by Wikis, Trackers or hierarchy driven CMSes.
b2evolution is free, open, and available to anyone under the GNU/GPL license.