It’s now common knowledge that there is a hidden club in Disneyland that serves alcohol, costs a mint to join, and provides special privileges. If you want to know more DisneyLandClub33.com is by far the website with the most comprehensive look at the most exclusive club at the Happiest Place On Earth. The fan built site has detailed history with personal stories from people who worked there. It has an extensive photo gallery. And it has a mystery.
Update: I have posted some further thoughts on this mystery.