If you thought Raspberry Pi is small and cheap, think again. Check out C.H.I.P. .. its a $9 computer… it runs on a Allwinner A13 cpu with 512MB ram and 4GB storage. It has one usb one micro usb audio jackthat can be used as vga output, wifi 802.11 b/g/n and bluetooth 4.0.
See it here : http://getchip.com/pages/chip