Mad props to @Br3akfstE4tr for the design and thanks for sharing the f360 file. I remixed this because the eggs my wife gets from her quail are just a bit too big for the original and while I was at it I made it print without supports and improved stability a bit.
The downside is these are a little bit bigger, so if size is a major issue you might like the original better.
Edit: On request I made one sized for medium to large chicken eggs as well; I haven't tested that, so if you print it let me know how it works. the f3d source is parameterized, so you could probably make one for xlarge eggs by just tweaking the eggDiameter and/or pedestalHeight parameters