Astronauts making s'mores in a fireplace on the ISS? Not likely, but if NASA ever did develop a portable fireplace it might look something like the Piet.
The Piet features a ceramic shell, brass reflector plates on the interior and a layer of rock wool fire insulation in between. It also burns ethanol instead of wood, so there is no smoke or soot—meaning that the open flame can be "safely" lit in the home. Of course, it doesn't look like it would take much for your drunken ass to knock over when you have a belly full of egg nog and s'mores over the holidays. [cavalliusdesign via MoCoLoco and Coroflot]