There have been some nice experiments to make a wiki behave more like a filesystem:
*[Integration of webdav and JSPWiki|http://codinginparadise.org/weblog/2004/08/i-added-webdav-to-open-source-wikiwiki.html]
*[Fuse filesystem for mediawiki|http://wikipediafs.sourceforge.net]

There quite a few obstacles in the way of a seamless solution:
* Windows seems to have made webdav optional
* firefox does not know how to handle dav protocol and Gnome does not allow to follow the links if the webdav is not already mounted.
* fuse is Linux-only