An extra leg
Here’s something you don’t see every day: a three-legged woman. You’d normally have to go to the circus to see such people, yet here we are, looking at a photograph of a beautiful woman with an extra appendage. We don’t mean to be rude, but doesn’t one of her thighs look thicker than the other?

Oh, wait, that’s a vase. She’s leaning a vase against her right thigh, and her right leg is bent underneath her. Okay, that makes a lot more sense. Now that we see the vase, it’s hard to see her with the extra leg. Never mind, there it is! Pretty freaky!