Round Christmas Lithophane that uses an E12 LED candelabra bulb/socket as the light source. I choose this because it gives great flexibility, I can use bulbs with varying Lumen values and there are a number of smart E12 bulbs available that allow for color changing/remote control. These are generally far less expensive than many of the other options I have found.
I created the Lithophane using https://itslitho.com/ There is a screenshot of my settings in the images but the most important is to ensure you use 97mm for all of the diameters and 4mm as the frame depth.
The lithophane 3mf file has a test plate that can be used to verify that the lithophane will fit in the base and top slots.