We know the Mayan calendar ends in 2012, maybe this is the reason! ;-)
Seriously, a large Coronal Mass Ejection ala the 1859 edition talked about here would probably put the world essentially without power and communication for MANY months! That might not be "the end", but it would certainly wake a lot of folks up to technology dependence ... and maybe wake up just a small shred of the idea that "Man is not REALLY the Measure!"
CME’s come in various sizes and velocities. CME’s aren’t intrinsically aimed at the Earth and could just as easily dissipate into empty space. Many CME’s don’t even make it as far as the Earth. But if conditions are right, CME’s can do a lot of damage. A CME hit Quebec in 1989 causing a nine-hour blackout and $4.3 billion in damages to the Canadian power grid. The mother of all CME’s in 1859 took down every telegraph in the world, causing arcing, fires, and melted wires in the equipment. Imagine what something like that would do to your PC or cellphone!