I can't find the thread where Brian was discussing distributing his talking newspaper.
Someone has developed a one-button audiobook player using the Raspberry Pi computer.
When you plug in a USB thumb drive with a special name/label, the Raspberry will stop playing, mount the thumb drive, deletes the old audio book, copies the new one, rebuilds the playlist and =96 after unplugging the thumb drive =96 starts the new audiobook in pause mode.
At the moment it just loads books off the USB drive, but probably a networkable version could be developed.