And that reasonable fear is why I'm in love with the voltmeter. :)

I've shocked myself twice, and both times I was just plugging something in. Once I'd wired up a very cheap plug and it shorted inside. The other time I was plugging in the stove, and that was truly terrifying -- luckily I had on rubber-soled shoes.

It's a bit more of a mystery, but I think there must have been a drop of water on my fingernail from the cleaning I'd been doing, which dripped at precisely the wrong time. The wall-wart is very, very small, so fingers are naturally close to the prongs.

Oddly, I'd been wiring in a new igniter, and everything I'd fixed worked fine!