I'm fortunate enough to be able to use our smaller spare room as a games room, it was the compromise I reached with my wife to keep my gaming stuff, films and various other collectibles out of the rest of the house
Got a 2 metre long table top running across the room, with another 1.2m table at the end to form an L shape. The smaller table at the end acts as my computer desk with my PC hooked up to a Monitor. Computer, PS5, Switch, Oculus Quest 2, Evercade and Various mini consoles are all on the table top with all my handhelds running along a shelf across the back wall. I've also got a 4K Samsung TV on the longer table top. Running above this are some storage units with Amiibo in them.
Underneath I've got my console set up with Atari 2600, PS1/2/3/4, PS Vita TV, NES, SNES, Gamecube, Wii, Wii U, Master System, Mega Drive/CD/32X, Saturn, DC, Xbox, Xbox 360 and Xbox One X all set up. Currently all are connected up to work at all times with the exception of the PS1, Wii and PS4. PS1 can be easily hooked up by swapping cables with PS2, Wii is basically just there so I'm not missing any Nintendo systems on the shelf (But I play them through Wii U), the PS4 has been unplugged since I got my PS5 but I store it there and move around the house if I need a blu ray player anywhere.
The older consoles run via SCART cables to my OSSC which converts the signal to HDMI and sends it to a Denon AV Receiver. The AV receiver has two outputs to both Monitor and TV so I can run things simultaneously on different screens or have different outputs to different zones. Sound is outputted to Q Acoustics Speakers/Sub which are set up on either side of the desk. Currently a 2.1 setup but I would like to add more speakers at some point although it's possibly overkill given the room is relatively small.
Got a computer chair for using at my monitor and a smaller sofa behind it for playing games via TV. Managed to pick up some themed cushions which I liked, wish I could find a SEGA one though. Got all my physical games/blu rays around the room in various units. Then there's another small unit behind the door which houses some more Amiibo plus a Virtual Boy, Famicom Mini, TV Colour 6 console and Game & Watch. Got all my extra controllers hung behind the door using shoe storage hangers. Works quite well. Additional cables are under the sofa.
It's definitely a bit crowded and busy but I like it and it's really functional
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