I have started writing a Perl CommunityProgrammedWiki based off of UseMod. It is now ready (I think). It should be possible to add most of the patches at UseMod:WikiPatches to [CpwWiki] in a couple of minutes (per patch). I invite you to try it out -- let me know if there are any bugs. The page [SpwTutorial] explains how to do it. (UPDATE: currently the actual reprogrammability is temporarily disabled due to my recent move. The wiki content is still there, so you can still discuss it, read the documentation, and get the source code, and later on I'll re-enable the rest).
[CpwWiki] is at: