@wardler
all electronic devices are required to go through the x-ray machine, including cell phones, some like laptops are required to be taken out of their bags and scan separately in their own tray
but why go through all the hassle of trying to shoe horn a bomb into another device, there's enough energy in a standard laptop battery pack to cause a nice little explosion, all that is required is to disable/remove the safety circuits and short the thing, the energy density of these things are ridiculous, and if you look at the tear down of an iPad 2 you'll see that thing is like 70% battery