I've recently acquired a Nvidia Jetson TK1 development board. It is $200 USD, and basically a Linux desktop system based on an ARM processor platform, running

I've recently acquired a Nvidia Jetson TK1 development board. It is $200 USD, and basically a Linux desktop system based on an ARM processor platform, running Ubuntu 14.04. You can easily hook up mass storage and other stuff. Just 2GB of RAM though.