Senior Societies
Columbia does not have any Secret Societies. If it does, then they're pretty damned secret because no one knows about them. Columbia does have two very low-profile Senior Societies, the Senior Society of Sachems and the Senior Society of Nacoms. Most students don't even know the societies exist.
Each society taps 15 juniors each year, the Sachems by luring the candidates into an ambush where he or she gets hit in the face with pie, the Nacoms by convincing the candidate that he or she is in trouble.
Society membership tends to reflect powerful student leaders across the campus, and some seats develop 'lineages', passing on from one holder of a leadership position to the next.
The Sachems were responsible for a 2005 prank in which the Lerner Hall ramps were decorated with saffron colored banners to mimic Cristo's "The Gates" installation in Central Park.
Commitment to secrecy
Shortly after midnight on 1 April 2007, after a partial list of members for the Sachems and Nacoms was created, WikiCU was hit by a seemingly coordinated vandalism attack by their members. The initial attack was at least kind of intelligent: Nacoms member Daniel Okin (Tokin84) and an unidentified user with a just-created account (RedLabel) first deleted all content from the pages, and then redirected the societies' pages to each other, creating an infinite redirect loop. Good SEAS thinking there!
About half an hour later, Sachems member Michelle Diamond (Mnd2102) stepped in and tried just deleting pages.
The administrators quickly restored order and banned the members.
Of course, pulling something as stupid as this (Daniel Okin's AIM is Tokin84 and Michelle Diamond's UNI is mnd2102) on a Wiki doesn't answer the question of whether they want secrecy or attention more.
Their commitment to secrecy is questionable. Current members take it very seriously, but many alumni put it on their resumes.