I'm using MoinMoin, which I also like because it stores its data in text files. MoinMoin has a "personal wiki" configuration that requires hardly any configuration and runs its own built-in web server. It also has a full-blown wiki with user IDs, access control lists, etc. that you can run under Apache or other web servers. I'm using it at work to store some documentation for my work group. (http://moinmo.in)