Airplane maker Boeing has unveiled what it calls the "The Lightest Metal Ever"—called microlattice, the material is a construct that is 99.99 per cent air. It has been developed by Boeing's HRL Laboratories along with colleagues at the University of California and the California Institute of Technology. The material has been developed as a way to reduce weight on airplanes or even rockets—a paper describing the development of the material was written by the team and published in the journal Science back in 2011—though the researchers have not yet revealed what sort of changes have been made since that time....