Check this out – apparently normal, everyday office paper can be turned into supercapacitors simply by dipping them in an “ink” of carbon nanotubes. The carbon nanotubes quickly absorb into the paper, hold on strong, and, when dry, hold quite a large charge. This means that many portable devices can be made even lighter, given that majority of their weight is caused by the weight of the batteries they use. Read more about it here.