There was a rumor going around about one of the sororities saying that they made a pledge sit between two sisters and eat an entire jar of mayonnaise and if she got any barf on either of the sisters she had to start over.
Supposedly one sorority had a file that contained Xeroxes each pledge had made of her breasts. Each pledge class had to make a middle of the night run to Kinko's and, um, copy themselves!
One sorority was rumored to have their letters tattooed on the inside of their thighs (this was back before tattoos were commonplace)