Naval engineer, Richard James back in 1945 had the idea for this simple toy when he dropped a coiled spring on the ground, and watched it bounce along. He later premiered his toy at a famous toy store in Philadelphia. It went on to be one of the most loved, and best selling toys of all time, netting him around $250 million dollars for his springy gift to children everywhere. You can’t go into a toy store, or even the small toy section of a grocery or drugstore, and NOT find a Slinky. They come in different colors, and materials now too, not just the original metal version. Still, the metal version is the best, because it goes slinking down the stairs better than the plastic ones.