@dodec Perhaps making such a box would be an interesting project at some point.
It would, but I'm hardly a hardware expert. I do software. Once this project is further along, though, I'd love to see it running "live" (it's still going to be Javascript-based and running in a browser, but the intent is to make an emulator for a computer that never existed).
@Rosemary
8x12 turns out to be a very comfortable pixel size for characters. It has just enough vertical room for diacritics without getting too smushed. Also, XenoTerm has 50 columns and 25 rows, which multiplies out to a nice 400 by 300 resolution, exactly proportional to classic television size. The right way to picture XenoTerm is as if you're watching it on a CRT with a rounded beige box hooked up to it.