I've been using Tikiwiki for a while — we have a site for a community currency in Montreal - CES Montreal.
I'm interested in getting involved in Tiki development: I've looked at other CMSs and Tikiwiki seems the most versatile and user/admin-friendly. As well, the community currency movement has a mod called cc for Tiki, and there's some other features that would be good that shouldn't really be added to the cc mod. Namely, I'm thinking of a sort of "Yellow Pages" for cc members, that could use tiki's categories, that would be a searchable list of offers and wants for cc members. This could be useful in other situations. If there's anything like that already, I'd like to know about it.