PBS’ Newshour has a gallery of Norbert Ostrowski’s amazing automotive design sketches from 1946 to 1973. “The designs were never meant to leave the studios. Automakers routinely destroyed early sketches for fear they would fall into the wrong hands. But some of them made their way out of Ford, GM and Chrysler, as well as now defunct Studebaker, Packard and AMC. According to one designer, they were smuggled out in boxes with false bottoms. One employee famously hid his sketches inside the liner of his trench coat.”