This MIT system allows a computer to move water droplets across a board.

Imagine drops of water sprinkled onto a pan's Teflon surface. Those droplets will stay in place, or move around if you tilt the pan from side to side, thanks to gravity. But researchers at the Massachusetts Institute of Technology's Media Lab have created a system by which droplets on a device follow a computer's instructions and move in a controlled way across the horizontal surface, like pieces on a board game.

The project was born out of a desire to "computationally reconfigure physical matter," says the project's lead, Udayan Umapathi, a research scientist at the MIT Media Lab. In other words, take a substance—in this case, water— and manipulate the way it moves with a computer.