Last week there was talk that the next step in airport screening would be body cavity searches, but there seems to be something even more invasive on the horizon: face scans. The Wall Street Journal, no doubt with a keen eye to the profit opportunities presented by the new paranoia, reports on the TSA's development of technology that will scan your face for any traces of a suppressed emotion, like a murderous impulse or extreme aggravation at yet another airport screening delay. Already in Knoxville, TN the TSA is trying out a manual procedure, first developed in Israel, in which screeners will look really closely at passengers and try to detect "vocal timbre, gestures and tiny facial movements" that indicate a potential terrorist attack. The next step is an interview in a closed room. What happens next is a little hazy: Guantanamo? The CIA rendition program? But don't worry: the company involved hopes to improve the screening process so that no more than 4% of innocent travelers are dragged off to the next stage in the terrorist inquiry. No figures on the acceptable number of terrorists making it through the system.