I've spent a lot of time looking at what wikis are running, and I've been particularly involved with one of them (Appropedia). I'd like to share a summary, relevant to web 2.0 and the built environment.
Appropedia could be called a wiki for the built environment. This is a platform, a site you can use for any purpose related to sustainability and development. It has a lot of pages of housing projects and designs, but is open for you to add any other construction, or urban design topic. (I'm very interested in urban planning, but haven't got around to starting pages on these topics).
Greenlivingpedia is also worth a look - not as big or active as Appropedia, but some very good pages on sustainable building.
Then of course there's Wikipedia, which has lots of useful information, but is very limited in the type of information you can add - no personal projects or designs, and nothing that can't be backed up by a "secondary source."
These three are the only active wikis I'm aware of with substantial content related to the built environment. There are lots of other wikis around, (e.g. the
Green Infrastructure Wiki, which is not very active). However it takes a lot for a wiki to reach a critical mass of contributors and content.
As an active Appropedian, I'd like to ask: what are your thoughts, and how can Appropedia serve a livable and sustainable built environment? What would it take for you to contribute to Appropedia?