Greg Copeland wrote:
On Sat, 02 Sep 2006 19:56:46 +0200, Mxsmanic wrote:

And the poles occasionally
reverse, which would also be somewhat of a disaster for
magnetically-based aviation.

It's expected the poles will flip sometime over the next couple of
centuries. For those of you interested in this phenomenon.
http://www.pbs.org/wgbh/nova/magnetic


Interesting, alarmist speculation.