What is the most innovative patent in your opinion?

Two, actually- There are two electrical connectors, with the patent held by General Electric Company, that are similar. These connectors were found everywhere prior to the age of the transistor, and are still found in refrigerators, stoves, and other electrical Appliances. The spade lug is a small piece of copper that has two fingers that slide under a nut around a screw, and has the other end of the copper formed so that it can be crimped around a wire. The washer lug is identical, except that instead of the two fingers, it has a washer that slips over the screw, and is then held in place by the nut. These devices replaced solder for connections, could be manufactured inexpensively, and did the job so well that they were the state of the art from about 1925 to 1975. Their utility is such that you will find them in most electricians tool boxes even today.