That sounds like an awesome idea if you can get it to work. Would it be easier to get a small computer- mini-cube or one of the flat ones from ibm- and graft the game console around it? I guess you could also get a ultra-portable laptop, which would fit into just about any console out there, and just pull the screen off.
I must say, keep us posted if this goes anywhere- Its a great idea!
im not sure if this is the correct category for this, but it seemed like to closest.
i am looking to install a computer in the case of an old game console, so i did some snooping, and to me t looks like the atari 5400 or 7800 systems have both the looks and the space for a nice computer install. any reccommendations on any other system to possibly use? also, if you have a decrepit system laying around, i am interested.

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