Seven years ago, I bit into a delicate variety of seaweed called umi-budō, or "sea grapes." I remember sampling a few dishes at Unjami, an Okinawan-style izakaya off Nakano Broadway in Tokyo (5-55-1 Nakano, Nakano-ku, Tokyo; 03-5345-5836), but the umi-budō stood out as something special. These tiny, grape-like beads are eaten fresh with vinegar sauce, and are unforgettable once you've had them.