There's a project called Raspberry Pi which is nearing the production stage now, which is a modern twist on the concept. There are plans to add expansion boards (to drive motors and other components off), and the units will retail at about $25. I'm pretty excited and I'm not a programmer or hardware fanatic. Just thought I'd post this because I know there are a lot of people who dabble in this kind of thing on here.
News Article
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Image of the PCB: http://www.raspberrypi.org/wp-content/uploads/2011/12/L1030067.jpg
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