New Scientists reports on the development of a lie detector that works by tracking blood flow through the blood vessels in your face. The system is being developed by (natch) the Us Department of Defense.

As I relax into the chair, the questioning begins. An automated voice instructs me to answer a series of questions with a simple yes or no. "Is your name Susan?" Yes. "Do you understand that I will not ask any trick questions on this test?" Yes. "Did you stab that woman downstairs this afternoon?" No.

Link
via [Boing Boing]