A Massachusetts mom who saw her driverless car rolling backward toward traffic down a sloped driveway—with her 2-year-old twins inside—did the only thing she could think of: "I had to use myself as a speed bump," she tells WCVB. It worked. Mindy Tran of Lawrence suffered a broken leg, and a dislocated shoulder and hip after lying down horizontally behind her Honda Accord, but she slowed it enough that a neighbor could hop inside and bring it to a full stop, reports ABC News. Police then used an airbag to lift the car off Tran, 22. (More uplifting news stories.)