It’s so cold that it’s hot.
Part 2: https://youtu.be/7zrx-b2sLUs
I referenced a lot of old videos in this one. Here they are, in clickity linkity form!
Chest Freezers; What they tell us about designing for X
Old-fashioned rice cookers are extremely clever
Reusable handwarmers that get hot by freezing
I also made passing references to
Forced-air Furnaces: The What, Why, and How
Portable Air Conditioners – Why you shouldn’t like them