My family is Jewish, but when I was much younger I managed to convince my parents to purchase address labels with this fish insignia (complete with Greek letters) on them. I must have been about 6 at the time, right after we moved into our new house, completely ignorant about all things Christian, and the conversation most likely went like this:

Mom: Look at all the little pictures we can get on our labels! Which would you like?
Me: (points to fish) I want that one! With the cute little fish!
Mom: Um... wouldn't you want something else? This one has a doggy on it...
Me: NO! I WANT THE FISH! (begin tantrum)
Mom: (sigh) Okay, fine, we'll get the fish.
Dad: (quietly, to Mom) We can't get the fish. What would our friends think?
Mom: (quietly, to Dad) We'll get these to appease him, and then get something else to use.
I found them earlier this year, a good 14 years after the fact. My folks never used most of them, for obvious reasons. Sure enough, in 1987 they bought another set with a script "W" (our last initial) on them, and used the script-initial labels most of the time. Occasionally, in my younger, stupid days, I would catch them applying the "wrong" label and affix a Jesus fish label instead. What did our friends think?

Yeah, I'm dense. I thought that WWJD was a radio station until I was in high school.