Jacob Appelbaum, a geek who is currently trekking in Iraq, posted this image of a roadside IED. The ringer is attached to the explosive trigger and the word on the street is that a GSM jammer would shut these things down pretty easily. We talked about this a few months ago, but this is an interesting close-up shot of one in the field.
https://gizmodo.com/riyadh-bombers-used-cellphones-to-detonate-6458
IED in Iraq [It’s complicated via BoingBoing]