Really smartarse title here
Whenever I got the calls that meant I had to travel a long way (not hard living in the middle of nowhere!) I would always insist that the person turn off any obvious power outlets and unplug the power cord and tell me if one of the metal prongs had a bright yellow line running down one side.
For the record, as far as I know, no Australian plug has ever had a bright yellow line anywhere to be seen.
Them: No, I can't see one on the plug.
Me: Is there one on the off switch when it's turned off?
Them: No, that's clear, too.
Me: Okay. Just try and replug it in, turn her on and see how it goes.
Them: Well, fuck me, it's working now.
Me: I bet it's those damn cheap power outlets.
Them: See you in the pub next time you're in the neighbourhood.
Works every time and no feelings are hurt.