Professor Liu’s lighter side

Today’s technological tidbit is this story about David Liu, a Harvard professor of chemistry who built a fleet of battery-powered airplanes that can stay aloft at speeds as low as 1 to 2 miles per hour.  The lightest of the aircraft weigh about as much as 6 paper clips.  He also built out of Lego bricks a catapult with a heat sensor that throws a toy mouse when it senses one of his cats passing by.