Gimpel3D is a free application that can help you convert a single 2D image or image sequence into stereoscopic 3D written by René Gimpel. Have in mind that this is not like the traditional 2D to 3D autoconversion solutions that do everything by themselves, you have to do a lot of things manually to make it work, but the end result can be much more convincing than that of an automatic conversion software. Gimpel3D uses a combination of traditional approaches as well as a proprietary projective modeling system that is used to actually remodel the 2D image into a something that resembles a true 3D scene that can be rendered into a realistically looking stereoscopic 3D image. The user works in true proportional space where the scene can be viewed from any location and the scene is edited geometrically in space using tools specifically designed to work with the perspective projection of the image. So in order to be able to work with this software, some previous experience with 3D modeling and animation software packages may be of great help. And if you are totally new into stereo 3D, then this software may be quite hard to understand and use, so you better start with something more automated.