Sure, but someone that wants to get a glass knife through airport security can come up with much better ways of doing it.
My dad and I occasionally play a game where we try to one-up each-other with ways to get weapons or contraband through security. There are a lot of ways. These backscatter scanners -- like most of the rest of airport security -- do very little to actually increase the security of the system.
It is sadly quite possible to get things through the xray machine... all it takes is forgetfulness on your part when packing carry-on, and inattentiveness on the part of the operator. Now, I didn't count on it happening a second time on the same trip, and sent the offending item home by USPS, but uh, yeah.
I'm all for security in airports - and I'm not even particularly bothered by the idea of naked pictures floating around - but I am completely uninterested in a security blanket. If stuff slips through so easily by accident, how hard can it be for a determined person? :(
My dad and I occasionally play a game where we try to one-up each-other with ways to get weapons or contraband through security. There are a lot of ways. These backscatter scanners -- like most of the rest of airport security -- do very little to actually increase the security of the system.
Also: http://xkcd.com/651/