Just think of how much more efficiently you could store your eggs if they were square! All neatly stacked. No more eggs rolling off of your plate, and they fit perfectly on a triscuit. Amaze your friends with tales of your new genetically engineered chicken. all this for a mere three dollars.
To use it, just hard boil your eggs and remove the shells. While they are still warm, drop one in the (preferably chilled) cuber and screw down the lid until the egg becomes square. Unscrew the lid and push up on the base plate to remove your now cubetacular egg. Repeat until you have a nice stack of eggs.