My floor lamp was causing a pretty glaring reflection when watching TV. This fixes that issue, while not looking too terrible.  

I'm not sure how common the dimensions are… Mine measured about 11.25in diameter across the top, and I didn't bother trying to match the profile curvature too tightly – figured it'd be easier to print without the steep overhang.

Note that I've uploaded both a .step file as well as the typical .stl. I'm able to get a much smoother curvature in the slicer with the step file, without any of the faceting that comes from the tessellating in the stl.