Boiler in a bottle: Shiny, contains fire, makes hotness.
This is also often called a volcano kettle. It's a one-piece pot and stove thingy, designed vaguely like a thermos bottle, but these things are useful only for heating water.
Some were used by Irish fishermen in the early 20th century, though other versions of the story vary. Anyway, damn clever lot, they. Another reason to love the Irish, if you're so inclined.
The place where you'd have your coffee stored is a firebox. The part around that, where the thermos bottle would have an insulating vacuum chamber, is actually a water jacket surrounding the firebox. Hot gases from a fire of burning twigs heat water in the water jacket as they rise through the central chimney and escape out the top. Kettles like these can rapidly boil water even in windy weather.
More names: Benghazi Boiler, Storm Kettle, Ghillie Kettle, Thermette, Survival Kettle, and so on.
More: "How the Kelly Kettle Works", and what is it, really? And some other stuff...
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Me? Getting all hotted up.