We've got a pretty spectacular red tide going in the waters off San Diego (and farther north and south). The organism is Lingulodinium polyedrum, my favorite dinoflagellate. Why favorite? Because it's intensely bioluminescent. When jostled, each organism will give off a flash of blue light created by a chemical reaction within the cell. When billions and billions of cells are jostled - say, by a breaking wave - you get a seriously spectacular flash of light.