Principia Discordia
The Principia Discordia is the foundational text of Discordianism.The full title is "THE MAGNUM OPIATE OF MALACLYPSE THE YOUNGER: PRINCIPIA DISCORDIA or How I Found Goddess And What I Did To Her When I Found Her, Wherein is Explained Absolutely Everything Worth Knowing About Absolutely Anything".
The book describes the Discordian society and its Goddess Eris. It features typewriter and handwritten text, pictures copied from other books, and lots of various stamps supposedly stolen from government offices as an act of spreading disorder. There are also some Fnords, but not as many as to make the reader feel uncomfortable.
The Principia could just be a joke, or series of jokes, but has value beyond making the reader laugh. Among other things, it reminds people not to take themselves too seriously.