I'm not tech savvy, but my wife's friend is a freakin genius. I was talking a year ago or so how I wanted to get one of those NES Classic Editions that had like, 30 classic NES games.
He was like- Why not just build one?
Of course I laughed at him but then he told me he basically builds these little computer systems (almost the size of your phone) that he can upload old games onto, and you can use your ps3 (or whatever) controller with them because they're bluetooth capable. You can also SAVE games at any point, and then reload them again. It's pretty badass.
Long story short, I have a little device that looks like this (see pic below), set up so I can play ALL of the games from Atari (both systems), Nintendo, Super Nintendo, Sega Genesis, NeoGeo, Turbo Graphix 16, and even Commodore 64. "Newer" type games on more involved systems take up a lot of room, so I keep my game library focused on the classics.

