One of my sorority sisters introduced us back in my freshman year and tried to set us up a couple of times - it always fell through, but I placed him in the "friend of a friend" category.
Near the end of my junior year (after each of us had acquired our psycho ex's - I think it's a law that before meeting Mr./Ms. Right you must have at least one psycho ex) I ran into him at a party at his dorm. We started talking, swapped phone numbers, and the rest is history
