I was always surprised that he never patented any! I remember the first one I saw as a kid introduced me to the idea of "planned obsolescence." Heavy stuff for eight. Back then, looking at MAD was like, as Sam Henderson has remarked, a kid getting a peek into the adult world from their cool uncle.
As opposed to the 80s onward, when instead they were writing down to what they thought teens wanted, resulting in the god knows what it is today.