John Titor

Although there is debate over the exact date it started, on November 02, 2000, a person calling themselves Timetravel_0, and later John Titor, started posting on a public forum that he was a time traveler from the year 2036.
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On March 21, 2001, John Titor told us he would be leaving our time and returning to 2036. After that, he was never heard from again. Speculation and investigation about who John Titor was and why he was online continues to this day.
Although it may be easy to dismiss all this as science fiction, most people who read his posts agree that there is something very haunting about John Titor and what he said. In addition, and open to more debate, he also made a series of predictions and comments that eerily seem to be coming true.

http://www.johntitor.com