In my investigations of wikis, open source content managment, and uses of these type of applications, I'm finding quite a lot of cools, "co-creative", or open source, sites.

First, the Echo Chamber Project.  This project, based on Drupal, plans to use a wiki, and other drupal modules, to create and offer "open source journalism".  Worthwhile to check out. 

Next up, The Transitioner.  Particularly devoted to the economy and co-intelligence, (topics like "open-source money"), but also included are knowledg, philosophy, community, and spirituality articles. This looks to be a straight Wiki, with a modified look.

Integrative Spirituality - Actually, this site froze me to my seat.  It is about integrative spirituality, has news, calendar functionality, polls, reviews, forums AND a wiki!  This is a PostNuke site, another open source CMS system.

I'm defnitely needing to find out more about this - supposedly the people for this meet here in San Francisco.  Two hesitations - for an "open source" project, when you enter, you agree that all content you post BELONGS to the site.  Why isn't this a Creative Commons license?  Also, on the calendar, the one event that is mentioned is an Andrew Cohen event in New York.  If this site is tied up with Andrew Cohen in a strong manner, not something I would be too interested in. 

FYI.  Lots of cool, wonderful participatory things happening.