Split double exposures can be a lot of fun. They essentially involve covering half of the frame and taking a shot and then covering the other half of the frame and taking another – both shots contributing to a single exposure. There are all kinds of ways you can do them, and Lomography even includes a “Splitzer” tool for this with their wide-angle Lomo’Instant camera.
But what about other cameras? Photographer Guillermo Hernandez has designed one of his own for the Instax Mini 90 that he made using his 3D printer which lets you accomplish the task quite easily.