Here is a structure that consists of 99.99% air, making it the world’s lightest metal ever. Microlattice is light enough to balance on top of a dandelion. The structure is strong though. It is a 3D open-cellular polymer structure that is hollow inside, so it can’t be easily crushed. Such material can make airplanes and cars more fuel-efficient.
The above video covers some of the applications for the Microlattice. More information is available here.