YouTuber TheCraftMaiden decided to make a Harry Potter Golden Egg, and it's a triumph of winging it when trying a craft project. It even has a turnable owl to open it.
The two most interesting items could be used for all sorts of cool projects: Worbla thermoplastic and shell-patterned styrene sheets. This is a pretty ambitious project even for an experienced crafter, so here's a great primer on Worbla:
• The Golden Egg – Harry Potter DIY (YouTube / TheCraftMaiden)