hehe
that made me laugh Knight.
Theres a trick to it. You put your face right close to it (so it sort of looks like your kissing the book...) and then slowly move the book away, keeping focus of the middle of the image. Hopefully as you keep doing this, the image will cross over, and both eyes will get the same pattern forming over them (This is how it works). In which case, the 3D image will then form, since each eye would be picking up a seperate part of the pattern that still remains partly the same.
It works in the same fashion as red/Blue filter glasses though not. Same principle.
Though a better example would have been those images you get on the internet meant for people with cross eyes, or ones with paraell vision to create a 3D effect, so basically an image side by side.
Each image or something in the image is slightly moved to the left or the right that is meant to be 3d, so when the eyes cross and move over each other, your brain picks up that one eye is seeing one image differently, and it creates the 3D effect.
If you close your eyes, you will see what I mean. Open one, and close that, and then open the other. You will find the nearer things are, the more it moves to the left or right, and so it works this way.
Hehe, I researched about 3D for quite a while when I was experimenting with it