Invisibility a Posibility??

An invisibility cloak that works in the microwave region of the electromagnetic spectrum has been unveiled by researchers in the US. The cloak works by steering microwave light around an object, making it appear to an observer as if it were not there at all. Earlier in 2006, John Pendry, a theoretical physicist at Imperial College London, UK, and colleagues showed how such an invisibility cloak could, in theory, be made. Now David Smith and colleagues at Duke University in North Carolina, US, have proved the idea works. The device only works under one type of wavelength and only in two dimensions. It has been shown to make copper rings simply disappear but hasn't quite gotten the shadow of the rings to disappear with it. Scientists working on this project are hoping to cloak 3d objects soon. What problems could arise from the creation of the invisibility? Do you think the creation of something such as an invisibility cloak would be helpful to society?