憂慮石 - 多種顏色與形狀

I keep one in my jacket pocket for when I'm stuck on hold or waiting in line—that thumb groove is just the right depth. It's small enough to not be bulky but substantial enough to actually feel like you're doing something. Already ordered a few more to give as stocking stuffers.

The thumb indent is smooth and fits nicely, so it does give me something to fiddle with during meetings. I just wish the colors were more distinct in person, since mine looks a bit washed out compared to the picture. It works fine as a pocket fidget, though nothing special.