Looking for a way to practise your wiki skills? Then why not sign up for camlibtm, Cambridge's very first librarians' TeachMeet...
We're using a PBworks wiki to organise the TeachMeet as that's where the TeachMeet central pages are. It's very easy to sign up and edit, and it a good way to have attendees manage the attendance list themselves.
As well as the Library Routes wiki mentioned in the Cam23 post, I've found some other interesting library-related wikis including recently the Library Day in the Life project and the list of blogging UK libraries and librarians. Wikis seem to work really well for amassing information when lots of people have something to add and everyone wants to see the results.
It is fair to say, though, that in thinking about hosting a bigger, better, TeachMeet in the future, we are considering having our own website or blog as the central online resource, because that would give us more control over appearance and layout.