RESTyFUSE is a straight HTTP based filesystem service based on FUSE and PHP.
The idea is to utilize a simple webservice that can serve up file content and the appropriate file system meta data to a client side filing system module.
It's not so much an alternative to the various DAV file systems out there as a simple quick and dirty file system.
You can install RESTyFUSE onto a server anywhere you have PHP and mod_rewrite (most Apache installs then).
You'll have to download it from CVS here at Savannah or download the DARCS repository at Tapsell-Ferrier's website.
Please see the README file in the source repository.
This seems like a useful piece of work to me. I'm considering building a real Linux VFS implementation around this. Why? Because I want a firewall alternative to NFS for installing machines. I also like the idea of doing my own G: drive.