It figures. Only after releasing the Arkham Book Club casebook do I really get an idea for replacing the tomes in Arkham Horror with a more fun mechanic.
These foldable tomes replace the tomes in the core Arkham Horror game. When you draw a tome during play, discard the tome card and pick up the foldable tome instead. The foldable tome allows your character to pore over its mysteries for days, learning spells and unique skills peculiar to the individual tome.
The link above shows the first draft of two tomes: Ludwig Prinn's terrible De Vermis Mysteriis, and the strange and alien Dhol Chants detailing a visit to the awful Plateau of Leng. More to follow.