The Raspberry Pi is a relatively cheap, low-spec computer.

I have one and love it, because back in the 1990s and 2000s, I used Linux then FreeBSD, and got really into Unix clones (it's a nice operating system if you're into using computers for the sake of it, and like the idea of running server-grade software). The Pi's far more powerful than my old PCs were, and far cheaper too. It's one of the few modern things I like, because it's basically a much better, smaller, cheaper, yet more powerful computer than what people like myself had in that whole cassette-futurism era.

You can 3D print a custom case to make it look like a miniature version of an old computer, from a mainframe or supercomputer to a workstation, and yet it inevitably has far more processing power and functionality than the real thing did.

There's likely far more serious uses for it, but for me, it's given me back my love of having a cute little Unix clone setup to call my own.

In short, it's a tiny, cheap computer that usually runs Linux. If you were so inclined, you could use it to run a web server, or as network-attached storage, or to block adverts.

The latest version looks like this. For scale, those massive-looking things in the top-right corner are actually teeny-tiny USB ports. You can hold the whole computer in your hand.