I once had a gyro gunsight from a WWII British Spitfire or Hurricane. From my mom's WWII collection. It's only function at home was basically a night-light. But it was pretty cool how they actually worked:
They were stored in a wooden box so pilots could install/remove this top-secret device. I had the box too. I had lots of pics years ago but not sure where they are now. I sold it to a collector in England. It was a real PIA dealing with customs in England because they classify such things as "military grade weaponry" unless you are clever with your description.