At Watzek Library, we're using a combination of static web pages maintained with the Contribute/Dreamweaver suite, Basecamp project management, and Google Docs to create/maintain our intranet.
I've been wanting to move us off static web pages and on to a wiki for awhile, but
I'm waiting to see what Google does with the JotSpot wiki platform. The beauty of the JotSpot wiki platform is that you could build applications on it such as simple databases, project management systems, etc. Basecamp is nice, but isn't quite up to Google Docs in functionality. Combining that with Google Docs could be pretty powerful.
Haven't heard much news on this front for awhile.