Some of the most truly horrible and bizarre diseases reared their heads for one specific moment in history before vanishing just as strangely as they arrived, never to be seen again (we hope).
According to the denizens of /r/conspiracy and your wacky aunt on Facebook, there are terrifying mysteries unfolding all around us, all the time. These people clearly don't use Google.
We love our serial killers in one of two flavors -- dead, or in prison. But not the third flavor: the ones who do their thing for years, or even decades, without ever getting caught.
