Airy, Airier, Aerogel. Until now, brittleness has limited the practical application of these delicate solids, which consist almost entirely of air-filled pores. This may now change: In the journal Angewandte Chemie, Japanese researchers have now introduced extremely elastic aerogels that are easy to process and can be produced at low cost. Their success relies on a doubly cross-linked organic-inorganic network structure with adjustable network density.