Don't urinate on downed power lines.
You might think that one's pretty obvious, but some poor schlub up in Washington state managed to electrocute himself by doing exactly that. It seems that Roy Messenger wasn't seriously hurt when his car collided with a power pole and knocked it down, but his car was stuck in the ditch. He called a relative to come and pull his car out, but when the family members arrived, he was dead. It seems that he felt the call of nature and answered it in the ditch -- and didn't see the downed live power line. Oops. The medical examiner said that the burn marks showed how the electricity traveled up the stream and zapped him. Can you say "Darwin Award"?
So, rule of thumb: If you should accidentally knock down a power pole, be very, very careful about what you do with your bodily fluids. Don't even spit!