Noah Shachtman in the New York Times:
One of the dullest grammar exercises is being used to help find potential terrorists, and save companies a bundle.
Diagramming sentences – picking out subject, verb, object, adjective and other parts of speech – has been a staple of middle and high school grammar lessons for decades. Now, with financing from the Central Intelligence Agency, a California firm is using the technique to comb through e-mail messages and chat room talks, which can be a rich lode of corporate and government information, and a tough one to mine.
More here.