We’re not talking about cutting edge technology here. I’m surprised I haven’t seen this before. It’s just a mug that plugs into the cigarette lighter in your car to keep your fluids warm (fluids not included).
It has a little display on the side to inform you of the inside temperature, and even has the decency to shut off when it senses the liquid of choice reaching molten lava temperatures, saving you from the potentially embarassing disfigurement.
It can be had for 29.95$ in a fine establishment like this one.