Keep The Cosmos On Your Finger
For those looking to outfit their heroes with a bit of flavorful bling, there's a fun article on Open Culture about armillary sphere rings. When folded, these precious-metal rings fit on one's finger (just like most other rings), but they can unfold to make a little armillary sphere, useful for astronomy.
The article also includes a dangerous link to a modern-day creator of these rings, in case I had an extra thousand-plus dollars kicking around.
-- Steven Marsh