Steam controller is fantastic, and unfortunately there’s really nothing else like it. I normally use a Logitech trackball, so the ability to use a touchpad like a trackball works well for me. I can’t think of any other controllers that use this instead of analog sticks.
I’ve actually stockpiled a few spares because I’m not sure what I would use as a replacement.
I’m not personally interested in the tech, but I could see it being relevant if your refrigerator is connected to the internet and you are at the store. You could find out whether to buy more or not.