Well, you can hook it up to just about anything that generates any kind of signal source and use it as a decoration. Just, like, plug it in across your computer's speaker outputs or something and you'll have an instant visualizer, for instance. Or even a household outlet, and you can see just how close to 60hz your mains power actually is on a second-by-second basis. I know plenty of people who have retro tube oscilloscopes kicking around above their computer desks purely for the mad scientist vibe, and this will be a lot cheaper than one of those...

They're cool, I used it as a volt probe a handful of times, or to check if a signal was moving (like, is the uart coming up at all).

I do chip/board bringup, it's a niche as hell usecase, I only used it if I didn't have a rigol around.

Later bought a portable hantek, it's basically a star trek tricorder, utterly amazing.