I recently put in a ceiling fan and didn't like the light bulb shades it came with - they were closed on the bottom and wouldn't fit on over the bulbs I wanted to use. Unfortunately, the shades I wanted to use wouldn't fit - too small for the set screws in the fixture to hold them in place.
So I made this spacer ring to put around them, which worked a treat.
The author marked this model as their own original creation.