Just found out the Oija letter-finder thingy is called a planchette!
here's the definition:
plan·chette (plan s̸het′)
a small, heart-shaped or triangular device, often having as one of its supports a pencil, that is supposed to write out a message or, as with a Ouija board, point to letters or words, as it moves with the fingers resting lightly on it.
Guess I should know that before I make art with it. ;-)