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@JimmyDansbo, for me, it already exists, and it's the Raspberry Pi. The Pi4 is a more than capable alternative for me. I use an 8GB model, running off SSD over USB3, and it's impressively fast. I use it for most of my Arduino and circuit design, and do a bit of gaming on it. I use the 3B+ for classic console emulation, and between the two that's good enough for my alternative.
That being said, I am VERY tempted to grab a
Atomic Pi, an x86 single board, so you have more OS, software options, and more horsepower to play with. It's powered by an Intel Atom x5-Z8350 quad core @ 1.44GHz with a 480MHz IGPU. It's limited to 2GB DDR3L-1600 RAM, but for my needs, that's more than enough. I want to use it for more demanding emulation, or see if I can get it running something like Win 95 OSR2.5, just for kicks. The big drawback is drivers for older operating systems, but I may still give it a go and see what I can get to run on it.