I'm running a mini-campaign in the world of GURPS Cabal.
Basically, the PCs are extremely low-ranking members of a worldwide conspiracy of wizards and monsters that wants to keep all things supernatural to itself (think the world of Harry Potter, when you consider what it actually means when the wizards casually mind-wipe the muggles...).
The campaign will take place over the holiday season of 1999, and the PCs will have to (among other things) search for the inheritance of Dietrich Eckhart (Thule Society member and personal mentor of Hitler) and try to banish an out-of-control Santa Claus (hard to keep magic a secret when there's Santa Claus flying over Frankfurt and deciding who is Naughty and who is Nice...)