I don't like to duplicate Slashdot stories but since /. doesn't include pictures, most won't have seen this anyway.
Basically, the idea is that lying causes blood to rush to the eyes, a technique that some say could be used quickly in airports and such. Put thermal detectors up that could get you images like the above ---
It's interesting, but relying on anything so inconclusive is a step in the wrong direction, imo.