Imagine you had a tiny box on your desk with every games console you've ever loved on it. A PlayStation, Dreamcast, Nintendo 64, SNES, Game Boy, and more, all squeezed into something you can fit in the palm of your hand. Well, you don't have to imagine it, because you can build one yourself for less than $100.
The Raspberry Pi is a tiny, affordable, customisable, and surprisingly powerful computer, and it's what I used to build my all-in-one emulation box. If that sounds daunting, don't worry.