Ben Heck, I have recently discovered your YouTube series and I believe have watched all of them. You've been getting my creative juices going. I've pondered building an arcade system using the MAME emulator for some time. But after being inspired by your builds and your love for legacy gaming, I thought I could dust off some of the old systems I have.
My idea is to build a standard arcade cabinet and install my various game systems: Atari 2600, NES, SNES, Nintendo 64, Game Cube, PS1, PS2 and Xbox, along with either an old PC or RaspberryPi running MAME. My thoughts around a build idea has to do with the ease of switching between the systems.
The thought is to have some type of dial or push button system under the monitor of the arcade that switches the Video, LR audio inputs to the monitor to the correct function. While this is simple enough, I would like to include at the "Marquee" portion of the arcade a digital board (such as the ones that you use for the pinball machines) that would display the various graphics of the system being played.
Other ideas include using your idea of the PC power supply to drive power most (if not all) of the systems, then port out the power and reset buttons to some type of key matrix that would be easily accessible as well. Lastly, I'm still thinking of ideas to have a standard layout for arcade style dual controllers that could be shared among all of the various systems.
Let me know your thoughts,
Fellow "Bengineer"
-Ben E.