Eliza is an older and not very smart conversation bot that talks to you by mirroring parts of your own phrases interspersed with stock phrases.
In this amazing experiment, Eliza was given an interface to AOL instant messenger and talked to a series of random strangers. It's amazing to see their misconceptions grow. Some people never realize anything, others quickly get frustrated and sign off, but none that I saw realized they were talking to a machine.
AOLiza