Marvell's SheevaPlug

http://www.marvell.com/products/embedded_processors/plug_computing_small_computer_digital_media/release/1256/

is a Zetera http://www.zetera.com box ---networked disks--- waiting to happen. You plug in a USB hard drive and your router. The wall wart (Linux machine) handles the network protocol. Your PC or the wall warts can manage the RAID if you choose that configuration.

Similar: http://www.ctera.com/home/ctera-cloudplug.html