I used to have a desk full of trinkets and doodads that frightened people. Invariably I'd grab a rubik's cube, slinky, or a yoyo and start fiddling with it.
That was when you knew I was somewhere else thinking of solving problems, or creating new things to do.
I scaled back my menagerie in recent years, but I still keep a few treasured trinkets around.
You never know when the next idea is waiting for you to reach for that familiar.