I present to you, a very spiky egg container.
I've been experimenting with using threads and getting the tolerance right on my printer, the first time you twist the two egg halves together it will be a bit stiff but after that it it should go together smoothly. Let me know if this is not the case for you. It can be scaled up with no issues.
Great for storing snacks, and because of the spikes it can be hidden in bushes and trees much easier than a round egg. Be warned though, it is surprisingly spiky,