Foam polystyrene egg cartons are a cool option that offer some neat features. They are widely used in the southern states to preserve the eggs longer than most other egg containers, where the heat and humidity can spoil your eggs quickly.
Foam egg cartons are also widely re-used by regular fresh egg customers since they can easily be sanitized. A sanitized carton can not only be reused for eggs. Need an extra ice-cube tray for a party? How about a vessel to make bath bombs! Need to store some jewelry for traveling? The options are endless!