Things you've bought that remind you of your unpublished book or another book

If I do stuff like this, it's usually for research purposes. For example, there's a small blue crystal ball that features in my series. Since the object gets handled and carried around occasionally throughout the story, I wanted to get a feel for its size, weight, what things would look like viewed through it, how it would be concealed, etc. I found one that fit the bill on Amazon and it wasn't too expensive, so I ordered it.

It's been helpful to have it handy when I write about the ball, but most of the time it sits on the shelves above my computer, gathering dust.

Readers have given me their versions of the eponymous Stone of the story - see the covers in my sig below. I have one that's an actual hagstone (a river rock with a natural hole worn through it), one crafted out of some kind of polymer resin (which, like the Stone, changes color), and one made of red jasper. It's nice to look at them and think someone liked the story enough to create something inspired by it.