Shelves of Infinity
From Tardis Wiki, the free Doctor Who reference
The Shelves of Infinity also known as Unit Zed-X4-one-9 was a piece of furniture created by the Assembers on Generios 8. It was said to be their greatest achievement. It was one of the Three Great Treasures of Generios.
What was so special about The Shelves was that the pieces (which kept appearing and disappearing) were able to exist in multiple dimensions. The instructions also kept getting longer. This it impossible to complete the task.
Melanie Bush and Banto Zame were able to obtain The Shelves of Infinity by tricking the Assemblers into thinking they had finished building them. (AUDIO: The One Doctor)