Another phenomenon some people worry about is space weather and solar activity. The fear is that, in 2012, the sun will reach the peak of an 11-year cycle known as solar maximum. When it does reach this peak on or around Dec. 21, 2012, the sun will unleash giant solar flares toward the Earth, causing unparalleled havoc.
This scenario is very similar to the previous one involving geomagnetic reversal, in that both pole shifts and solar activity occur at fairly regular intervals. Solar flares will likely happen sometime between 2012 and 2014, but they've been happening for years and years, and the worst they can do is interrupt satellite communications.