Hi, I've modified the RioPlay firmware to move the database onto the rio itself. No more server software! I need some brave people to try this thing out. http://www.mikewinter.org/musicmuppet/
With this firmware, the rio will spider a URL and gather all of the mp3, read their tags, and insert them into an internal database. Other than this, the firmware works much like the original rioplay.
Please try this out and send any bug reports back to me!