Australian physicists devlop water tractor beam It's a really brilliant idea that seems dead obvious once you know about it. As soon as I saw the headline I knew how there brilliant folks were doing it. Rogue waves at sea are made when constructive interference occurs between waves of different length. my modulating the movements on their wave generator they can generate two different waves (or more) simultaneously and ensure that the object that they are looking to manipulate ends up on a standing wave driving it where they want it to go. Probably never be feasible on anything bigger that a dingy, but oil cleanup is what interests me the most. There may be a similar technology being used for ultrasonic manipulation in air.
