Viruses that could kill the power around the world

It has been said that computer viruses that are out there that they have effected the business world computers greatly. It has cost many of business millions of dollars to fix these problem. People have compared these types of viruses to turn off the power to people. It made me think about the the new television series, Revolution that is now its second season. Revolution is about a the power to the world getting shut off. Throughout the series you learn that it was tool to save electricity that was turned into a weapon to take away power. The weapon did not work as they expected and turned off all the power in the world. In the series you find out that they way the power was turned off was through little computers that act like viruses and draw electricity from anything that can produce power. The series really makes me think that something like this could happen. The government is always trying to come up with weapons that will give them power over the enemy. There could be some type of weapon out there that is in testing and force something to go horribly wrong. It does not have to necessarily be a global black out. I have not heard of any weapon that is out there that could do such thing but we always need to keep an open mind about these things.