SIRDSy
Single Image Random Dot Stereograms are images where a 3D illusion is encoded by shifting pixels in a repeating pattern. The image is viewed by "looking past" the image and having each eye looking at a different instance of the repeating pattern. Dots at the top of the image are included to help. You look past the image, and the two dots should become 3.
You can generate different sterograms by selecting or uploading depthmaps (black and white images indicting 3D information), and tiles.