Move over, Legos: there’s a new brick in town. The robotics department at MIT has developed a new kind of self-assembling block without any external parts. The simple-looking cubes are actually super-advanced robots that can come together to build modular machines, changing depending on what is needed. Each block has a flywheel inside to give it momentum, accelerating to up to 20,000 rotations per minute and then suddenly breaking in milliseconds. When that happens, all the energy transfers from the flywheel into the cube structure, causing it to flip into position as if by magic. The cubes can roll, climb walls and even jump. Just don’t introduce them to Skynet.