[whpalmer4]

You don't need an box running Mac OS X Server, a plain old Mac running 10.4 or later will do.

It also shouldn't be too terribly difficult(*) to get a suitable WebDAV server running on a Linux box -- isn't Apache available for all of the usual distros? That's what you are configuring with the instructions mentioned above, the only difference being that there's a bit of GUI to control starting and stopping the server. The configuration file stuff shouldn't be any different, to the best of my recollection.

(*) he says, not having tried it :)