In the 2006 movie "The Illusionist", starring Edward Norton as a turn of the century magician in Vienna, Austria, Norton makes a special locket and gives it to his love. The locket opens to display a picture, and may also be turned to form a heart shaped locket. When the heart shaped locket opens, a different picture is displayed. The functioning of the locket appeared for just a few seconds in the movie, and the scene was created by the use of two lockets and special effects. The locket in the movie only opens when in the heart configuration. That brief glimpse of a magical locket inspired lots of people to try to buy one, and inspired a number of craftsman to try to make a locket in the real world that worked in the same way.
A short video of the locket in action:
Duplicating the action of the locket from the movie in the real world was actually a very difficult task, and the lockets made were all crude, and only partially functional. An ebay search will turn up quite a few which "kind of" work, but not really. That changed when Jim Anderson designed a locket that actually works similar to the magician's locket,or even better. Pictures show its operation below. All these pictures are of the same locket.
It uses tiny magnets that both repel and attract other tiny magnets, which cause the locket sections to float over certain positions, and snap into place in other positions. It also uses an intricate ball socket that allows the locket to achieve the seemingly impossible, and required some intricate machining.
Jim sells these lockets at Illusion Lockets. They are available in many types of wood and other materials. They come with a small punch to punch out round portraits from prints.