I’ve got this idea bouncing around in my head for a follow-up to Epic Summer which involves [yet another] fictional secret society. Though this one is much more in the mold of the spooky Skulls & Bones/Illuminati pastiche of powerful men in shadowy corridors with secret knowledge. So I decided to do some research, and see if there were any real (or, at least, believed to be real by someone) secret societies that I could appropriate for my own ends.
Anyway, that led me to this fascinating Wikipedia list. Originally I was skimming as many names as I could to try and locate a promising one, but eventually I just started reading the ones that looked interesting. And hot damn are some of then interesting. Check out the Knights of the Golden Circle.