The vita and the Wii U both fit this for me. I feel like neither of those gained a ton of traction and lost support pretty quickly despite having some great titles and ideas.

I’ve never played a sega cd, but I can agree somewhat with the Saturn. It seems like a pretty cool system whose short life is mostly forgotten about.

I don’t know if it’s underrated, but I do enjoy the Turbografx-16 quite a bit. It’s definitely not as good as Nintendo and sega’s offerings, but I still like playing it. I also though the hu cards were really cool as a kid.