Dragon Egg

The Enderdragon Egg is an item first mentioned by Notch on the 27th of October, 2011 on which Notch is supposedly working before the release. Sharing its name with the Enderdragon, the item and the mob may be related to each other. However very little information has been made available on the purpose of the egg thus far.

Trivia

 * Enderdragons drop a single obsidian block as of 1.9 pre-release 5. Since obsidian blocks are already present in abundance in The End and serve no direct purpose in The End as of yet, it is unknown whether the obsidian block is a placeholder or not. Even so, it is unknown whether the Enderdragon will continue to drop the obsidian block, or at some point the egg or another item in the near future.
 * It's not yet known if the egg will be an item, a block or some kind of entity. It remains to be seen if the egg will have a purpose of it's own or if it will serve as some kind of ingredient.
 * People think that the Enderdragon egg will be able to be hatched in the overworld, and since it is not in it's natural habitat, it will hatch into a red dragon.