It will be interesting when this becomes avaliable for fettlers like us:
http://www.popsci.com/science/article/2010-03/new-polymer-conducts-better-metals-only-one-direction
One way thermo coupler.
http://www.popsci.com/science/article/2010-03/new-polymer-conducts-better-metals-only-one-direction
One way thermo coupler.