Swik by SourceLabs is really awesome. It’s part wiki and part search engine. I first heard about it through the Django page, but have since poked around and there’s a lot of great information there. There’s a plethora of information on Ajax and related technologies, platforms, and projects. Swik is also folksonomy-enabled (buzzword++). For example, here’s the framework tag, python tag and java tag.
It’s a great little service.
SWiK has been updated, with new Zeitgeist features that show what is happening in the community at this moment. Please check it out, thanks.