Erotic Silhouette Optical Illusion
Try looking at the reflection and see if she reverses direction. I shift my focus to the side and can tell in my peripheral vision that she has changed direction, I then move my eyes back on the silhouette and walla she is rotating in the other direction.
What is even more amazing is that if you see her spinning clockwise then it is her right leg and arm that is up in the air, but if you see her spinning counter-clockwise then it is her left leg and arm that are up in the air.