Pepper's Cone: An Inexpensive Do-It-Yourself 3D Display
This is a "3D display" in the same sense that a curved monitor is a "3D display" because it exists in three-dimensional space. The actual image being displayed is two-dimensional (ignoring the red-blue anaglyph gimmick).<p>I think it would be more accurate to just call this a transparent heads-up display.