Useless Information: Eveready Batteries
A good article about the story of Joshua L. Cowen, a man smart enough to devise a variety of inventions, none of which were really big commercial successes. One of them was a scheme to make illuminated flower pots, but he became bored with the idea and gave the project to a subordinate who worked for him as a salesman.
The whole flowerpot thing didn't really work out, but the technology used to light the pot was reworked, and developed into what we now call "the flashlight". The company (American Eveready) that made these earned six million dollars over two decades, a nice chunk of money even now, but it was a huge amount at the turn of the century.
Most people might be upset that they gave away this kind of gravy train, but Cohen had other ideas coming down the track. He used the battery technology to power a toy train set, originally sold as display units for store windows. But demand for home use of these sets quickly followed, and by 1907 they were a common sight under the Christmas tree. Joshua "Lionel" Cowen ultimately made more money from this, than the business he gave away, as well as becoming an almost iconic part of the holiday season.