The Body Deck
This is the body deck, a deck of playing cards where each card is a coronal slice of a human body. We made it because everything's better with a skinless man inside, and because poker's more fun when you're learning anatomy. Go Fish is more fun when you feel like Victor Frankenstein. You'll be getting one soon if you're subscribed to the Curiosity box.
But this began as an idea I had a few years ago when I was trying to visualize a fourth spatial dimension. I can turn a shape into its mirror image by rotating it in a higher dimension, but I can't rotate this guy in a higher dimension because I can't access the fourth. However, a higher dimension rotation is like taking something's front and back and smashing them through each other.
I can do that with this guy because he's sliced. Right now, his left arm is raised, so his reflection's right arm will be raised. Now see that his back is on top? Well, if I reverse the order of the cards, I will be putting his back on the bottom and his face on the top. Without turning him around, he is now raising his right hand. He can become his own mirror image in real life. Oh yeah, yeah, yeah! By the way, the hearts do contain the heart.