Aerogels finding new applications

Silica aerogels are extremely low-density solids nicknamed "frozen smoke" that hold the record for being the best insulators known. Their widespread adoption could dramatically increase energy efficiency in many areas of technology. While their production costs are still prohibitive for everyday uses, their potential is being realized more and more within industrial applications.

Wired News: A Solid That's Light as Air
Wikipedia - Aerogels

Aerogels made out of carbon can store an incredible amount of electricity for their size and are generating interest especially among those developing hybrid cars.
Aerogel Composite Announces ENERGel(TM) Ultracapacitor