Skynet (Terminator)
http://en.wikipedia.org/wiki/Skynet_(Terminator)#Origin_and_Nature
Shortly afterward it gained sentience and the panicking operators, realizing the extent of its abilities, attempted to shut it down. Skynet perceived the attempt to deactivate it as an attack and came to the conclusion that all of humanity would attempt to destroy it. To defend itself, it came to one conclusion: Humanity must be terminated.
Sure, worrying about the Zompocalypse might be trendy and all, but I feel it’s more prudent to focus on the Robocalpyse. Google is watching.
