To protect it from spam we wanted people to sign in before being able to edit pages, but we didn’t want to ask our coworkers to create yet another account. Since all our coworkers have a cobot account already we spent an afternoon adding OAuth support to gollum, which is an open source wiki system developed by the guys at github. OAuth is a sort of programming standard that allows different web applications to work together, and since cobot supports it, we can use it in our wiki to sign people in. Now when someone clicks the Sign in link on our wiki, he gets redirected to cobot, presses a button and voila — is magically signed in at the wiki.
If you want to do something similar you can use our OAuth enabled version of gollum, conveniently called gollum_oauth as a starting point (it’s written in Ruby), or you can just install it to have your own cobot enabled wiki.