Spider silk is nothing short of an engineering marvel. Weight for weight, it's stronger than steel and tougher than Kevlar. But spiders are disagreeable creatures. Unlike the silkworms, they've proven unwilling to bow to humanity's domestication, but that hasn't stopped scientists from stealing the secrets. In this episode of Stuff to Blow Your Mind, enter a world of spider silk medicine, nanomaterials, optics, music and of course transgenic goats.