It's no secret, at least to my philosophy students, that my favorite atheist is Friedrich Nietzsche. Were I an atheist (I am not) my "Bible" would be Thus Spoke Zarathustra, as it was for Jack London and Eugene O'Neill.
Here's another nice little article on Nietzsche's enduring cultural influence, generated out of U-Wisconsin historian Jennifer Ratner-Rosenhagen's American Nietzsche: A History of an Icon and His Ideas.
