In Chennai, India, a group of criminals run an amazing long con: they set up their own fake police station. I think a lot of GMs (myself included) underestimate exactly how much people will be able to believe. Would you let your players get away with something like this?
Speaking of justice, here's a look at a modern study that tests the validity of physiognomy, the theory that personality is reflected in one's face - sounds delightfully Victorian, doesn't it? My favorite quote:
Lombroso claimed that certain features indicated particular types of criminal…[His] technique was widely used in Europe until the 1930s. Prosecuting lawyers could claim that a flattened nose was a scientifically proven sign of a thief, thus strengthening their case.Imagine pulling that one on your Call of Cthulhu players!
Urban exploration is possibly the closest we come to dungeon crawling in the modern west, and sewers are a perennial favorite for urban adventuring, so here's an interview with Toronto explorer Michael Cook that I came across. The pictures are especially nice. Here's a similar piece on a secret society of catacomb explorers in Paris.
Not everyone explores modern dungeons for fun, though. There's a society of homeless people living in the storm sewers under Las Vegas.
Last, Telecanter dug up this description of an amazing heresy: human sacrifices offered up to St. Vitus, portrayed as a four-headed man. Too often, GMs don't consider how religions in their games can change or mutate over time, sometimes drastically.
I've actually got one more story—the largest star ever discovered—but I'm saving that oen for a full-on article. Stay tuned!