Zero Days" that I watched on the recommendation of a daughter. It investigates the detection, effect and alleged origin of the internet work publicly called StuxNet but known to the authors as "Olympic Games".
StuxNet was modified to aggressively spread itself but was originally highly targeted at industrial controllers connected to computers running Windows. The specific controllers ran nuclear fuel refining centrifuges.
When activated, the malware would spin the centrifuges until they were physically damaged.
What's interesting about cyber warfare is that it is a new kind of weapon which does physical harm to an enemy without it being obvious what happened and who the attacker was. It's clear that developed countries, with highly connected industrial control grids are highly vulnerable to this new kind of attack.
If our power grid was disabled by an external attacker, (for example), would that prompt a "kinetic" response?
I rented the movie on iTunes and highly recommend it.