Robert Patch of Chevy Chase, Md., was only 5 years old in 1962 when he designed a toy truck that could be converted into a flatbed or a dump truck by altering the placement of the axles. His father, a patent attorney, saw that the truck’s design was unique enough to be patentable, so Robert signed the application with an X and had the mark witnessed by a notary public. When the application was granted, Robert became the youngest person in history to receive a U.S. patent.

The publicity meant nothing to him, but it did bring one benefit. He had made his working model from bottle caps, Scotch tape, nails, and old shoe boxes. Someone at US Keds, the shoebox brand, saw the story — and sent him a new pair of sneakers.