Mike Greenstein is giant of a man. He can pull a truck uphill using only his teeth. They call him the Mighty Atom Jr and he has perhaps the strongest jaws and neck in the country. But at 5-foot-4, this 91-year-old Second World War veteran is a surprising powerhouse. To celebrate the Fourth of July, he demonstrated that he still has teeth of steel by dragging his Buick down 48th Street in midtown New York City live on Fox News.