Dick Sprang’s ‘Secrets of the Batcave’ Art Is An Encyclopedia of Bat-History
Back in 1995, legendary Batman artist Dick Sprang produced a lithograph for DC called "Secrets of the Batcave," and it is awesome:
(Click to Bat-Size)
I'm pretty familiar with it (my old boss used to have a signed copy hanging in the store), but it wasn't until I was looking at it today that I realized just how much Sprang worked into the art...