It's that wonderful yet disconcerting feeling you get looking at an Escher print, or a Dali in the painter's trickster mode. It starts in the left brain, but then right-brain magic takes over. The eye sees it, but the mind can't quite believe it. Now multiply that times 12, and you've got a calendar that showcases a dozen of the world's best visual puzzles. Al Seckel, a neuroscientist at the California Institute of Technology, is one of the world's leading authorities on, and collectors of, illusions that open a window into the workings of the human mind. Now, for 2004, he takes the imagination to exotic places, where half of the fun is being fooled, and the other half is figuring out why. There's "The Impossible Terrace"--are you looking at the structure from above or below? "What Is This?"--the unretouched photograph of a human figure in a position so bizarre, you won't understand what you're looking at. The Rubik's Cube that proves colors aren't always what they appear. And from artist Shigeo Fukuda, a seemingly abstract sculpture of kitchen utensils creating the shadow of a perfectly formed motorcycle. Each astounding image is art, science, and a little bit of magic rolled into one.