The hard work, tenacity and ingenuity of inventors and their inventions are celebrated. Some inventions, such as the zipper or crimp crown bottle cap, helped revolutionize specific industries, and thus made their inventors wealthy. Some inventors start with a problem which they hope to be able to overcome with an invention. Some start out with materials for which they develop new uses. In both cases, not all inventions work out, due to among other things poor design or impractical uses as seen by the public. The United States has perhaps been home to more useful inventions than any other country. Obtaining a patent allows an inventor seventeen years exclusive rights to an idea for an invention.