This is another good reason for securely grounding a circuit before working on it.
Generators aren't all that common in my area, but those who have considered one have often tried to go down the "just connect it to the nearest wall socket" route.
The price of a transfer switch and proper installation has deterred quite a few, although I don't doubt they've gone with the exdtension cord route.
I bet that Haywired Tom was really pleased with that pass-thru idea!
