One of the advantages of the internal-combustion engine (or the external-combustion engine, for that matter) is that you get vast amounts of waste heat for use in making the vehicle's passenger area nice and toasty when it's cold out. However, an increasingly large group thinks that an engine technology that squanders two-thirds of its energy on waste heat leaves something to be desired, so legions of engineers are now working on plug-in hybrids and full electric cars. Thing is, without all that hot water coming out of the engine all the time, how do you keep the vehicle's occupants from freezing their tuchuses off while at the same time refraining from sucker-punching the batteries by making heat in the same manner as your toaster? Antarctic-grade parkas will do the job, but the engineers seem to think that the next generation of thermoelectric semiconductors are the way to go. [MIT]