One of the things I remember being in the stores as a kid during deer season was a round orange seat warmer. This was a relatively inexpensive, unpowered cushion filled with some kind of insulation that kept your bottom warm when you were sitting in a deer blind, riding in the car or watching a late season football game. However it was built, it was very effective - you could put it between your hands and feel the heat between them. It was notable for having a crunchy feel to it, for having a distinctive plastic smell out of the bag, and for being absolutely bright blaze orange so that you could never be mistaken for a deer. 

Some of the oldest ones have great drawings, like this one for a boiler for a heater for railway cars in 1881.

There was a lot of work done around the turn of the previous century on keeping people warm - this is an article from Cassier's Magazine of 1893 showing how the transition from coal to electricity started happening:

There are to-day in the neighborhood of 150 patents on electric heaters which alone goes to show that considerable attention has been paid them by the inventors. A very large number of these patents apply to the heating of cars. One of the earliest applications for patents on electric heating apparatus filed in 1869 by Burton specifies that one of the largest applications of this particular heater for which patent is applied is that of heating railway carriages by means of heated metallic plates placed under the feet of passengers.

The challenge is to keep yourself and your travel companions warm without having something inadvertently catch fire. With all of the advances in insulation technology since the invention of the vinyl orange hot seat, I'm hopeful that there's some more stylish cushion I could put in my office chair.

Edward Vielmetti is on the move in Ann Arbor, Mich., because it's too cold to sit down. Reach him at edwardvielmetti@annarbor.com.