Source: engadget.comResearchers from The University of Tokyo have demoed a touchable hologram at Siggraph 2009. The project, called Touchable Holography, involves the use of Wiimotes placed above the display to track hand motion, and an airborne ultrasound tactile display created in the university's lab to create the sensation of touch. The result is a holographic image that produces tactile feedback without any actual touching, and without degrading the image itself.
Touchable Holography (no audio)
Video from: YouTube.com
Article from: EnGadget.com