Conductive nanotube film.
By now, any of you who are paying attention have seen news of this.
Nanotube sheets come of age
Apparently they are also conductive. This strikes me as an ideal replacement for ITO (Indium Tin Oxide) conductive coatings which are used, for example, on the surface of photovoltaic cells. This seems really VERY promising for the next stage of photovoltaics. One of the articles I've read mentioned solar sails as another application. Other cruder applications have been mentioned as window heaters and incandescent light sources. Good stuff...