I remember viewing Wikipedia before it became the Wikipedia we now use. I consulted the Wayback Machine and got this result. It's hard to believe that was just 6 years ago!
What are wikis good for? They are great for staff who want to contribute to an ever-changing work environment, for internal use. They are great for outreach to the community, to get library users to contribute to a topic (I see a wiki here as a group blog).