Here’s one I came across by accident. In 1979, Susan E Brownlow patented a small ‘cool box’ in the shape and size of a cigarette packet. There’s a removable section at the bottom which you can put in the freezer, and the box is insulated so that you can carry it in your pocket and the contents are kept cool.
The motivation? People giving up smoking need something to chew on which doesn’t include too many calories. Carrot sticks are apparently good. But how do you carry carrot sticks around with you all day and keep them fresh and crunchy?