My uncle once had a trailer that he just ran some quick power to with an extension cord or something and somehow screwed up cause I went to the doorand touched the metal side. YOWCH.
That was _our_ trailer when I was a kid! Was never properly grounded somehow (my dad wasn't that great with wiring as it turns out), and for _years_ you had to remember to jump up when opening the front door if you were barefoot and it was damp outside. -- Jim