Mochi is a Japanese food, made by pounding glutinous rice to a paste, then drying it in slabs. These are then cooked on a griddle until they are crisp on the outside and really gluey on the inside, and are served wrapped in a strip of nori (dried seaweed). You can find them at carts in the Ginza (Tokyo's main shopping district) after dark.
Japanese mochi is made of white rice, but American health-food mochi is made with brown rice, and sometimes raisins and cinnamon. The main (only?) U.S. manufacturer is in Berkeley, California (of course). Mochi cooked by this recipe turns out fluffier and less gluey than by the Japanese method.
Feeds one or more, depending on the size of your waffle iron.