Peel and slice cucumbers into very thin slices. Sprinkle sliced cucumber slices with salt and let stand a few minutes. Squeeze out excess moisture. Combine vinegar, sugar, and soy in a bowl and mix well. Pour the vinegar mixture over the cucumber slices and mix well. Serve in individual dishes.
May add Wakame (seaweed), crab, and shrimp.
Recipe courtesy Tomoko Moriguchi