Well, telling you is cheating but maybe it will spark your interest.
Project Lifelog was something DARPA was working on for the CIA.
"The objective of the LifeLog concept was "to be able to trace the 'threads' of an individual's life in terms of events, states, and relationships", and it has the ability to "take in all of a subject's experience, from phone numbers dialed and e-mail messages viewed to every breath taken, step made and place gone""
The project was discontinued in January 2004.
Facebook launched in February of 2004.