How do you see ships without a pricey radar system? The question has troubled seaports around the world as they work to improve security. Without radar installations, it can be hard for port employees to detect small ships like those employed by pirates or by the terrorists who attacked the USS Cole in 2000. A team of researchers in Germany can now offer security teams a new option, though: putting existing cellular towers to work as quick and dirty radar systems.Developed at the Fraunhofer Inst...