Researchers have discovered that the world's oldest sex toy, found in a cave in Germany, was used to heat things up in places other than the bedroom. They say the 30,000-year-old siltstone phallus doubled as a tool to ignite fires. From the article: "The prehistoric phallus, which has marks where it was obviously used for striking against flints, also features carved rings around one polished end. Researchers say it's easy to see what it was used for. The scientists pieced together the multitasking tool from more than a dozen fragments found in a cave complex linked with the activities not of the Neanderthals, but of modern humans."