This device lets you take 3D anaglyph photos and movies with an ordinary camera. The parts cost about $30. It's pretty simple to build and you don't need any special software or camera equipment. Please let me know if you have any improvements on this design.
Newsflash! The photos below show a slide viewer that allows you to view a single slide with both eyes. It might have similar optics to the device in this Instructable. I suggest trying the following:
1. order a slide viewer on e-bay for $10-20. 2. cut the viewer in half along the slot for the slide. 3. cover the eye holes with the red and blue colored filters. 4. put your camera where the slide goes and take a photo.