Recently shopping for fridges, the biggest frustration I had was with egg storage. I could not find a single fridge where the egg holders did not commit the sins of ugliness and uselessness. As a staple of my kitchen, the egg should not be retained within an ugly generic hunk of plastic but should be celebrated as is the bread tin or the milk jug.
As for uselessness, I've seen fridges which can hold 10 eggs - presumably I am going to eat the rest of the dozen immediately and raw? In fact, even being able to hold a simple 12 eggs is not sufficient for me, as I usually buy my dozen when I have 1-2 of the last pack remaining. No, my egg holder must be able to scale up and down to meet my egg devouring demands.
Hence, the egg-centric egg holder was born. Holding 7 eggs in a single layer (or 4 more in a daring egg-crobatic pyramid arrangement!) the egg holder has a hexagonal arrangement for optimal packing. Grabbing the outer faces of the egg holder and lifting the tray up reveals the second nested egg holder which can be placed on top of the first loaded layer (or next to the first if you have enough fridge space) for a total of 14 eggs (or 18 in a pyramid). When not in use, just nest the holders back together for optimal space utilization.
3D printable and immediately usable straight off the bed, I hope you find this design egg-celent!