Never heard of it. I have never seen a "rubber duck" except in the hands of Erny on Sesame Street, let alone held a conversation with one.
I have frequently found "Confessional Debugging" to be incredibly useful. I suppose, if I didn't have a human being to hand, a rubber duck would suffice. Honestly, it doesn't have to be someone who understands code, it can be the dumbest 2yo blond you ever met, or even a pet. In some ways, this is better, because it encourages you to speak in more simplistic terms, and the problem is often that you are looking at it too technically.
I suspect a 2yo, or pet dog / cat would be better than a cardboard Linus Torvalds, Bill Gates, Rob Norton or Steve Wozniak. Because you would be looking at those cardboard cut-outs for inspiration.
"What would my hero do?" Where explaining the problem to one who you do not expect to know the answer will make you "dumb down" the situation. You usually forgot something a 2yo would have considered obvious. In fact, it's probably the very fact that it was so obvious that caused you to forget to inform the computer about it. And we all know how stupid
they are.
I do tell my cats all sorts of silly things, sharing my day with them and imagining what they have got up to while I was at work out loud with them. Answering their cries based upon my imagined understanding of their meaning, and even "Silly Daddy. He thought you said you where hungry, when all you really wanted was a clean litter tray." But I don't think I've ever tried to explain my code to them. I suspect I have said "You wouldn't do it like that would you? I'm sure you have a much better algorithm in your head to solve that one. If only the keys where paw sized." when they are looking at the cursor bouncing across the screen sat between me and the keyboard.
: They just look like they are intently reading the code.