Here is a new holographic projection in air. It is physically permeable and interactive. http://youtu.be/QSCO4di-E3U
air
Air hologram
IO2Technology is showing how a floating in air hologram is not the future anymore. The costs are still high.But then...
fogscreen
https://youtu.be/YkXedK0C2p0 In this setting an interactive video image is projected on a thin layer of air.