Just came across
this and thought of this thread. I don't think it's out yet, some places say it comes out in march, but I wasn't able to find anywhere selling it yet, although I didn't look too hard. It's a tiny computer that can run windows 8.1 on an Atom processor (IE should be able to run the DS). It's a bit more pricy than a Pi ($150 for the windows version), but it should work. You'd need to get a display that can take HDMI in, a USB hub for all your inputs, an Ethernet to USB adapter so that you could hook up to the FMS, and you'd probably want to get a battery/UPS to power it so you wouldn't have to boot it up every match (I'm guessing it doesn't have an internal battery). Overall the setup probably wouldn't have to be too different from one for a pi in terms of the components necessary.