This isn’t a gadget per se, but it is hard to classify CONCRETE THAT TRANSMITS LIGHT!!!!!!. The technology uses an embedded solutions of fiber optic glass so in reality it is not really “concrete” so to speak, but is as strong as concrete. This would be so cool to have in my room.
“Thousands of optical glass fibers form a matrix and run parallel to each other between the two main surfaces of every block,” explained its inventor Áron Losonczi. “Shadows on the lighter side will appear with sharp outlines on the darker one. Even the colours remain the same. This special effect creates the general impression that the thickness and weight of a concrete wall will disappear.”