Here is my setup...

I have a USB drive on the boxee box.
I turned on the server and smb services on the bb, using the default settings.
I find the bb & drive over my network, using normal connections.

At first, I tried to lock it down with a user name and password but had way too many issues, so I went back to defaults, restarted both bb & pc.

It now works.... Yeah!!

Now, I can add movies, nfo, thumbs, whatever from my pc to the bb.

That's all I need for now.

Now off to Walmart and best buy to get a antenna so we can cut the cable!!