I’ll go first.
When I was a kid my family had a TI-99/4A. The 99 series was Texas Instruments’ only real foray into the PC and video game market, and it failed to be competitive with Commodore, Atari, and Amiga. Most games were booted from cartridges.
My favorites were Hunt the Wumpus, a sort of early survival-horror with a turn-based grid system, and Alpiner, a mountain-climbing game with various hazards, kind of a reverse SkiFree. It also had the ability to read data from cassette tapes to load text-based games. The one I remember is Hammurabi, a sim/strategy game which I didn’t really get as a kid. Now that I’ve gotten into strategy games like Civilization and Romance of the Three Kingdoms it would be interesting to revisit.
I own a Virtual Boy. Not really super rare or anything but definitely obscure. Other than most people I love playing with it! Wish it had more games.
My best friend from high school had one with a broken stand/tripod. Everything else worked fine but you needed to lay on your back and balance it on your face, and end up with a big red ring around your face after. I remember Wario jumping from foreground to background and back.