One for the Pagan/New Age crowd.

http://www.stonehengeusa.com/Events.htm

What is the Harmonic Concordance?
The ancient people, the Mayan calendar, Native American elders, all seem to have recorded this date in time. According to the elders, all the Stargates will be lined up and activated on the planet in the coming event known as the Harmonic Concordance. With the help of Barbara Hand Clow and her Bear Publishing Company, Jose Arguilles published a book in 1985 all about the Harmonic Convergence. Arguilles found a prophecy in the Mayan codexes that if 144,000 people could come together on August 17, 18 and 19 of 1987, and greet the dawn in peace, harmony, prayer, meditation and love, that ALL of the dire predictions of mass death and destruction in the coming age could be pulled down by a factor of ten.