Each one of these coasters features a different slice of a theoretical human brain. When they’re stacked up, they create a 3D rendering of a human brain, which is sure to impress your guests with even a passing interest in, well, anything cool. They come in a set of 10, and stacking them in the right order should be easy considering they’re labeled. Made from glass, each coaster also features small rubber feet to keep them off your surface, and away from scratches. At $20 for the set, it’s an inexpensive way to let your guests know that you’re into science-y stuff.