And you know the 3D printers that make cool plastic products? Well, now they're doing the same thing, but with metal. The European Space Agency's printing metal parts for their spacecrafts that are lighter, stronger, and cheaper than conventional parts. Their goal is to build a satellite out of a single hunk of metal--no welding or bolts required.
And money does grow on trees--in the form of gold! Scientists in Australia discovered that you-Eucalyptus trees actually contain gold particles. The roots dig so far down into the earth that they sometimes tap into gold deposits. And finding new deposits of the precious metal are rare. It's dropped 45% in the past decade.