Java Edition:Work in Progress
From 15w33c to 15w40b (1.9 snapshots), the end city ship didn't have its elytra yet. Searge left a book inside the ship saying "We will have something else here soon..." signed by him. This is only discontinued if your world is singleplayer (unless you're Searge, in which case, hi!) or is whitelisted/blacklisted and Searge isn't allowed to join but nonetheless it is a cool item to obtain. Before Searge's book, a beacon would generate inside the end ships.
Obtaining
End City Loot
Inside the end city ship, there is an iron ring in the basement with a hopper. Inside the hopper is the book signed by Searge titled Work in Progress.
Copies
Written books may be copied in 13w36a (a 1.7.2 snapshot) and above by crafting them with a book and quill. 14w05a (a 1.8 snapshot) added the generation tag, which increases by one each time the book is copied. The three variants that can be created are "Original", "Copy", and "Copy of a Copy". Books that are a copy of a copy cannot be copied further. All books created before this point and newly signed books will be considered original.
Gallery
Inside text of Searge's book
The hopper within the end city ship which has the Searge Book within