How can sewage sludge be turned into gold? What can powerful x-rays reveal about ancient scrolls that were torched by the eruption of Mount Vesuvius in 79 C.E.? And which genes control the size of different brain regions? Producer Meghna Sachdev chats about these stories and more with Science’s Susanne Bard. Plus, Myrtha Hässig discusses the surprising heterogeneity of comet 67P as part of Science’s special issue on the Rosetta spacecraft.