The voice of Siri comes from a real human being. Susan Bennett in Atlanta, Georgia says she's the original voice of Siri, Apple's automated assistant, and an audio expert backs up her claim.
In an interview with CNN, Bennett says she's been doing voice over work since the 1970s - she was the voice of Tillie the Teller, the first ATM, and she's often heard in airports and on phone systems.
Bennett says she recorded the voice parts in July of 2005 for what became Siri. Apple has not confirmed that Bennett is the original voice. 
- Rob Archer