An American small business, Next Thing, have made a small computer, called CHIP. Total cost for it alone is 9 dollars. You then have the backboard with a 1GHz Allwinner A13 CPU, a videochip, a full USB port, a micro USB port, Bluetooth, wifi and 512MB RAM and 4GB storage. It'll be pre-loaded with a Debian based Linux.

If you want a separate (but on-clickable) VGA port, that's an extra $10, while HDMI is an extra $15.

Fully open source. You can download the schematics and build your own.
See https://www.youtube.com/watch?feature=player_embedded&v=XkfBWAJ7kbI for the video.
Or check their Kickstarter page for all the info you need.

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