Bentogram box is a hologram projector kit, which is can be bought at any toy store and allows you to build your hologram projector at home.
There are Pyramid and Z hologram.
Pyramid Hologram is able to show a video in 4 sides but the area to display the video is small.
Z hologram shows the images better by expanding the height between the base and the screen to place the glass screen at 45 degrees between the base and the projector or digital screen