This is something very small, but I feel like I should have known it by now. On German and English keyboards, the "Z" and "Y" keys are in the opposite places.
I knew there were extra characters for accented vowels -- but I'd never noticed the Y and Z. Makes perfect sense, though -- Z is a much more common character in German than English, while Y is much less so.
(By the way, isn't that Torpedo handsome? The one below is my favorite. Via.)