And, indeed, it turned out that FreeBSD's standard drivers work quite happily with it, though it took a bit of looking in documentation from two different network driver files to figure out why -- the controller chip on it is a clone of a fairly standard one. Unfortunately, though, I couldn't get a connection; it would ping itself, but not the rest of the world, and the "connection" lights didn't come on.
Eventually, I figured out why. It's an ethernet card, and a hub, on a single board. And so the ports on it are "hub" ports -- and so, to connect it to my real network hub, I needed to use a crossover cable. For some reason, this seemed rather amusing; I'm not sure why. (Sadly, it's only a 10Mbps connection, so it's not actually much use as a hub.)
Also, I picked up a couple of game controllers to play with. I'm a bit confused by them, though -- they're standard original Playstation controllers, down to the "Sony Playstation" logo and the SCPH-1080 part number. But, instead of having Playstation (nine-conductor) cables, they've got flat six-conductor flat cables that look like heavyish-grade phone cables and terminate in an ethernet-style plug. Anyone have an idea what those might go to?
They're also rather interesting on the inside; I hadn't realized just how little electronic circuitry was required to convert fourteen buttons of input into a serial data stream. It's just a couple of tiny 8-bit shift registers (half a square cm each) and some resistors.