I've recently been testing the many cores of the MiSTer and recently thought about something that could be interesting to see on here. I wasn't sure where exactly to put this because it's not really a game console, but it also definitely has that capability and that is the Ti 83 and 84 graphing calculators. I think many of us as students had one of these and didn't just use them for their graphing functionality.
I know they use the Zilog Z80 cpu, and it would be quite interesting to see how the software that runs on them compares to other systems using the same chip. Just thought I'd put this out there.