Wait, you got zapped at your in-laws' house? That sounds like the worst time to learn that lesson. Was their wiring really old or something? Kind of a scary way to find out you need the right tools.
Yeah, "scary" is the right word for it. My uncle had a lamp that would shock you if you touched the metal base, just a little tingle. He kept saying it was fine until his cat brushed against it and yowled like it was dying. Turns out the whole thing was live. Some stuff you just don't mess with.