John Robb quotes an article in the WSJ (registration req.):

Using cellphones to detonate bombs remotely.  This isn't a new technique but it has now gone mainstream. The simplicity and power of the technique promise extensive use in the future.

Terrorists in last week's attacks in Spain apparently hooked up bombs to cellphones, which theoretically could have allowed them to detonate the explosives from the other side of the world. Hooking up a phone to a bomb also provides the option of using an alarm clock in the phone to detonate the explosive, which is how it appears one unexploded device was set up.

Which reminds me that the RATP (the Parisian Transport Authority) has invested massively to provide GSM coverage on most of Paris subway, and is now investing to provide Wi-Fi coverage as well. Why use cumbersome phones, that require one to steal smart cards to operate them, when you can just use the Internet and hide like a vulgar spammer? How long before we see an IP-enabled bomb?