Reva Keston patented this “chewed gum receptacle” in 1949. “It has always been a problem for those addicted to the habit of chewing gum, when tired of chewing, where to store the same until again wanted or as to how to finally dispose of it.” Keston’s solution was a cardboard blank scored for folding: Impale your gum on the barb, fold up the flaps, and you can carry the wad around unstickily until it’s wanted again. “The receptacle may be carried in a purse or pocket or it may be provided with a safety pin for attaching the same to a piece of clothing.”

This would have been handy in Singapore, which has banned chewing gum since vandals began sticking it on the door sensors of MRT trains in the 1990s. No gum can be bought or sold inside the country. “If you can’t think because you can’t chew,” said former prime minister Lee Kuan Yew, “try a banana.”