usb drive and ftp
Plugged in a 2TB USB drive to the FireTV, installed an ftp server on the FireTV, put cyberduck (ftp client) on my Windows 7 machine.
Now I can create directories on the USB drive on the FireTV from my Windows machine and ftp files into those directories. XBMC sees them fine and plays them.
I cannot ftp any file over 2GB it fails every time (no mater if ftp or ssh or different client on the Windows box.) I CAN add files over 2GB to the USB drive if it detach it and plug it direct into my Windows machine and transfer the files. Then the FireTV and XBMC can see those files and use them normally.