I had a strange experience with electric shock.
After parking my 5er in its storage spot (no connections of any type), I was draining the hot water heater to change the anode. Upon touching the water, a shock ran through me - not alot, but enough to be noticed. Thinking it was a fluke, I tried it again multiple times - each one with the same result.
Then I looked up and realized what was going on - our storage spot is under a set of high power lines. The power lines are inducing a current in our trailer and was flowing through the water being drained (and me!)
As a pipeliner, I shouldn't have needed several tries to figure this out - it is a well known and understood phenomenon in the industry. Guess I'm a bit slow.