Bob Woodward, in a recent interview, alluded to a top secret "sophisticated and lethal special operation program" developed by the military to track al-Qaida leaders in Iraq. Sharon Weinberger of Danger Room speculates the program he's referring to may be 'Tagging, Tracking, and Locating,' which creates a 'human thermal fingerprint' at long distance. More here(1).

1. http://blog.wired.com/defense/2008/09/whats-the-milit.html