The concept of the hula hoop had been around for centuries. Then, in the late 1950s, Wham-O, a maverick California toy company, rolled out a plastic hoop for swivel-hipped kids. The concept caught on and 25 million sold in the first six months. They cost $1.98 each, and, by 1958, 100 million of them had been sold around the world -- except in Japan and the Soviet Union where they were said to represent the "emptiness of American culture." Ouch.