The Cyberiad: Fables for the Cybernetic Age by Stanislaw Lem

Stanislaw Lem is perhaps the most original and influential European science-fiction writer of the twentieth century.
The Cyberiad, one of Lem's most beloved works, follows the exploits of the Trurl and Klapaucius, two ingenious 'constructors'. In their adventures through a strange medieval universe they encounter a machine capable of creating anything that starts with the letter 'N'; kings who oppress their people with parlour games; and PhD pirates who demand ransom in knowledge rather than gold. It is a world where UFOs land silently on lawns at dawn, and where even the stars can be re-arranged for advertising purposes.