Danish company ViZoo developed the Cheoptics360, a 360 degree holographic video display system.

Cheoptics360 is a four-sided pyramid manufactured of transparent material so the audience can see through it from every side. Inside the pyramid chamber the audience can see objects that seem to be freely floating video images and computer graphics.
This is done through surface mirroring and reflections. The pyramid itself is used as a kind of prism that assembles light from four video projections into a solid image.

The system looks pretty impressive, especially because of its rather large dimensions. We reported about the Heliodisplay holographic system in the past, but the 3D display is much smaller compared to the Cheoptics360 XL.
Watch this video to see the Cheoptics360 XL in action.
More details on the Vizoo site and on the ramboll site.