El Jugador Open Source Game Console
Okay, it's not perfect for robotics, but I've been working on this one for about a month and I'm pretty proud of it, so I figured I'd share:
El Jugador is a retro open-source game console based on a Parallax Propeller & designed as module to fit on top of the Propeller Platform.
* SD Card bootloader so no programming hardware is required
* PAL or NTSC Video Output with Audio
* 2 Controller Ports
* Make games in C, spin, or assembly
* Modular so you can add other things like battery packs or protoboards.
* Open Source under the MIT license
* Overclock-able up to 200 MIPS with a 6.25Mhz Crystal
What kind of games can I make / play on it?
Your imagination (and your skill) is really your only limit - A few demo videos are below. In terms of graphics, I would say it's on par with a TurboGrafx-16. Better than an NES, but not quite as clear as an SNES. Not all games take full advantage of the graphical power, of course.
More info, sample videos, schematics, and layout are on the project page.