I was forced to change my network password the other morning.  No big deal.  However, around lunch I noticed my iPhone battery life was down to 17% (from 100% at 8:00am).  I had forgotten to update my ActiveSync password on my iPhone after the change (which seemed to cause the phone to continually fail to sync my e-mail and killed my battery).  In the future, I’ll need to remember to change both passwords at the same time.