MoinMoin is an advanced, easy to use and extensible WikiEngine with a large community of users. Said in a few words, it is about collaboration on easily editable web pages. MoinMoin is Free Software licensed under the GPL.
Give this a shot, worked for me. Will work on making a better interface for it and embed in a app I am writing called ChunkyGTD.
Changed the location of the Data Directory from:
This should allow the Backup in the PortableApps Menu to backup your content.