Actually, you can do this. what you need is webdav. http://www.webdav.org/
We use it for editing stuff at work because it lets the remote folks use their own high speed connects to get to the server instead of having to dial into our LAN.
It's the shiznit, but mozilla doesn't support it. You can use Amaya to get to it, or dream weaver has dav support built in too.