Yes, you’re looking at some kind of KVM switch. You can get VGA cables that are up to 100 feet long, I had to get some big-ass ones like that when I used to have our computer in another room from our projector. USB hubs let you run almost arbitrarily long USB cables, so that’s what you’ll do for keyboard and mouse, and of course sound cables are no problem.
The VGA cables will be the expensive part – big long ones can get pricey. Shop around online, Google the hell out of it. Measure exactly how long you need it to be and then add five feet. Practical limit will be around a hundred feet before you start getting signal distortion on conventional shielded cables (actually, you’ll get some blur at anything over twenty feet, but for games it should still be OK). You can get VGA signal amplifiers to handle unbounded distances, but then you’re starting to talk real money. I think the cables I got were like thirty feet.
The big problem of course is that you’ll have to go to the computer itself to switch it to whatever monitor you want to use…
Hell, I might actually still have one of those long cables. I’ll look in the garage when I get home. If I do, I’ll sell it to you for 30% off the best Google price you can find, you pay shipping.
How many remote stations are you actually talking? If only one, then a cheap KVM switch would work fine. If more, it’ll cost more.
Also, don’t you have a girlfriend or something? Check with her before drilling holes through the floors and walls. My wife wound up vetoing all visible cabling (which torpedoed the rear surround sound speakers), which actually was a good thing once we had kids – long runs of visible cables + young kids = VERY BAD.
Final edit: you can do the same thing for a 360 with VGA output. I actually have a nice 2x2 VGA switcher – I have my PC and my 360 as inputs, my projector and monitor as outputs. So if my wife wants to watch a 360 movie on the projector while I game on the PC, it’s two button presses and we’re there; or if I want to play a PC game on the projector while she plays 360 on the monitor, we can trivially do that. Can’t remember where I found the switcher online either, though. It was only about $150 which was a really low price for a switcher.
Aleck: Smart Displays would have been worthless for gaming – not nearly enough speed.