Our Design Director at work brought "egg carving" to my attention a few weeks ago. I didn't even think such a thing was possible given how fragile egg shells are.
We just happen to have a dremel lying around, so I received a quick crash course on how to use it and started making holes in my egg. It took 2 different bits, one to make the initial hole and another to carve outward from the hole. The shell is surprisingly resistant. I got a bit too bold and tried drawing an S curve, which resulted in the big hole.
My first attempted ended abruptly since I didn't want noise complaints from our neighbors about someone drilling at 9:30pm, but hopefully there will be more refined attempts to come!
Wear a mask, or work in a well ventilated area so you don't risk breathing in salmonella dust! Either that or find a way to sterilize your egg shells beforehand.