Scientific article about backscatter technology (and it's shortcomings). Ouch, TSA, really... found first on slashdot.
http://tech.slashdot.org/story/10/12...-Easily-Fooled
Juicy quote:
It is very likely that a large (15–20 cm in diameter), irregularly-shaped, cm-thick pancake [of PETN explosive] with beveled edges, taped to the abdomen, would be invisible to this technology. ... It is also easy to see that an object such as a wire or a boxcutter blade, taped to the side of the body, or even a small gun in the same location, will be invisible.