That's still a good idea, thanks.
I could pick up an old 486 from a local resale shop, for peanuts. Then, I could add a couple of NICs, and a switch... but I'm down to the same amount of money.
I'd rather go that way, but I think I'll start with something simple, and "upgrade" later.
Here's an add-on twist: I might build a server, for image hosting, and/or for setting up my own webpage and/or website (I'm aware that it's not as reliable as having a site hosted). I may even add a file server.