There are lots of robots that try to replicate human movement. But we're especially excited about robots that don't just mimic human function but add to it — like this attachable cuff that gives your hand two extra, functioning fingers, that work along with your existing five.
Just like your fingers move in concert to grasp objects, the two robotic fingers are also meant to move together. Using both a series of sensors that track the movements of your fingers and an algorithm meant to predict patterns of human motion, the robotic fingers can sync up with your other fingers to help pick up objects or just to stabilize them. (It's take on stirring creamer into a cup of coffee one-handed, which you can see above, is particularly cool.)
Although this version is just a prototype, the MIT researchers who built the bot are already planning on a future version that would be just 1/3 of the size that you see in the video. At that smaller size, they say, that they could turn it into a watch or bracelet, where the robotic fingers could remain folded up until called on.