The questions of what it means to be alive is something that humans have puzzled and puzzed over for years. Descartes came up with "I think therefore I am" but because he said it in Latin, no one took him seriously.
Fast forward many years, and computer heads started thinking about how do we tell if a computer is alive (you know, like in the Terminator movies), and a guy named Alan Turing came up with what is now known as the Turing Test. The idea is pretty simple: if you sit in a room and 'talk' to a computer (over, say, IM) could you tell if the writer on the other end were a computer or a person. If you can't tell, then the computer has passed the Turing Test.
I'm very happy to report that this bar has now been crossed... if all humans were Sarah Palin. Using an analysis of her word usage in speeches and interviews, this site randomly generates Sarah Palin-like answers. Quite accurate, really. And scary.