The Seven Society

Yale's Skull and Bones is probably the best known collegiate secret society, but for sheer drama and spectacle, none can top the University of Virginia's Seven Society. No one knows exactly when or how the group formed, but it dates back at least to 1905, when its symbol — the numeral '7' surrounded by alpha, omega and infinity signs — first appeared in the school's yearbook. The society's roster is a closely guarded secret; membership is only revealed by a banner at the member's funeral. The group seems to be more progressive than some collegiate societies, at least in terms of gender equality. While Skull and Bones didn't vote to allow women into the club until 1991, the identity of the Seven Society's first known female member was revealed in 1958.

The group's highest-profile activities are elaborately presented donations and gifts. According to the university's Virginia magazine, the school's 1947 commencement address was interrupted when a check for $177,777.77 floated to the ground when the smoke cleared after a small explosion. In 2008, a $14,777.77 contribution was delivered 'by a skydiver carrying a large 7 flag'.

If you want to contact the Seven Society, you'll have to get into the spirit of their famously clandestine activities. The group only accepts correspondence in the form of a letter deposited at the Thomas Jefferson statue in the school's Rotunda.