Mix one part science fiction, one part misunderstood Mayan history, one part Hollywood movie hype, and quite a bit of public credulity, and what do you get? A new wave of doomsday hysteria that is causing scientists to step forward to reassure the public that the world is not, actually, going to end on December 21, 2012. The rumors flying around the Internet offer a number of ways in which the world may end, including a planetary collision and changes to the Earth's rotation or magnetic field, but they all agree on that date of doom. You can bet that the viral marketing campaign promoting the upcoming planetary disaster movie 2012 has a little something to do with the recent uptick in paranoia.