Just a quick list of some weird books that I love and that people usually don't know about:
A Course in Hypnotism, found in my grandfather's library, written by some unknown dude who offered the course through mail.
Pinpoint of Eternity by Peter Salm, about representations of eternal points in Western literature.
Bartleby and Co. by Enrique Villa-Matas, about writers who almost never or never wrote.
The Life of the Cosmos by Lee Smolin, about how the laws of the universe might have evolved through some sort of natural selection, just as living things did.
Marta, The Tree, and The Clock by Jorge Andrade, a collection of the plays of the Brazilian playwright.
Finite and Infinite Games by James P.Carse, an elegant and compelling meditation around two ways of living life, the finite and the infinite way.