I have always wanted some Aerogel, and I am not sure why? Maybe just to hold something that is 99.8% air, or to try and figure out something to make with it. NASA seems to have found some uses for the amazing stuff. They have been successful in collecting cosmic dust samples, and insulating the Mars Pathfinder rover.
Aerogel can be very expensive and the prices vary greatly across Internet. Recently I found a relatively low cost supplier. You can get granular samples from United Nuclear for as little as $5. If you purchase a sample and make something cool, don’t forget to post it in the MAKE Flickr photo pool. – Link
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