Designing a different / customized kind of computer system?

I've read about how when you Install the windows OS onto a usb stick It's unique to that computer (b/c of specific drivers, specs, hardware etc... and yes, It Is possible with some tweaking, don't spout out propaganda you're fed from Microsoft and apple). I'd like to know what it would take to design a generic computer that all you would have to do is plug in your personal drive and your OS (whichever it may be) and files are programs all there ready for use. And also be made in such a way that if the 'terminal' were duplicated part for part, no matter which one your drive was plugged Into It, would work the same. I'm thinking of designing a kind of system like this- drawing on elements from sci-fi (which is obversely based on the real world) In Stargate Atlantis and Battlestar Galactica (reimagined version). In Stargate Atlantis, Atlantis Is a cIty-shIp that has In Its Infrastructure the hardware, database, and OS, which is accessible from the hundreds of terminals throughout; each one is like a separate pc but are all connected to the database and processing power of the city as a whole. In a similar way, In Battlestar Galactic, the Galactica class Battlestar has a closed network which they rely on Instead of wireless to prevent cyber-attacks from the cylons... but the only advantage I care about Is that data transfer Is much faster via wires, and fiber optic cable even more so. With the amount of products and parts available on the market today, budget is the only limiting factor. I know many people are programmed to say, "It’s not possible" or immediately shoot it down by saying how hard it would be, and that I should just buy a computer and be happy. But I am not just a consumer, I’m an artist, a designer, I’m not going to let other people call the shots just so they get a profit. Now I know Linux has the sort of open source availability I like, but I’m not too familiar with It and I’d like the project to be user friendly as well as geek friendly If the user so chooses (like an optimized combination of apple, Microsoft, and Linux). I will no doubt read around at the library and online, but I wanted to hear from people who already have experience and know what I’d be better off learning and what I’d be better off skipping altogether.