Last month, a "hologram" of Tupac Shakur performed two of his songs with Snoop Dogg at the Coachella Music Festival.
Since Tupac is actually physically dead the news of the digitally alive Tupac swept the internet like wildfire.
A similar technique was used at the 2006 Grammy Awards showing Madonna with the virtual members of the band Gorillaz onto the stage in a "live" performance.
While headline grabbing these performances actually used an illusionary technique called a Pepper's ghost, which has origins as far back as 1584.
Here's one schuchnet built at home...
What's a Pepper's ghost?
Pepper's ghost is an illusionary technique used in theatre, movies and magic tricks. Using a plate of glass and special lighting techniques, it can make objects seem to appear or disappear, or make one object morph intoanother. It is named after John Henry Pepper, who popularized the effect in the mid 1800s.
The Pepper's ghost is often confused with holograms, which are a lot harder to create and come in a variety of formats, from your VISA card to the illustion of a 3-D object floating in front of you.
So what's a hologram then?
The two main kinds of holograms are reflection and transmission.
Reflection holograms create images by reflecting light from the front, while transmission holograms work by bending light from behind through an interference pattern recorded on a photographic transparency.
Everyone knows what a Hologram is, they've seen one in Starwars, R2D2 showed Princess Leia begging for Obi Wan Kenobi for help.
There is no current method of creating a hologram in open air, but the idea is so embedded in peoples mind we keep getting asked to create Holograms by clients.
But the effect can be simulated by projecting an image, or a series of images for the correct 3D effect, onto a physical medium like smoke, glass or spinning perspex.
Click Suite experimented with this hologram simulation of a moa skeleton back in 2007 using a moving image projected onto a water vapour screen.
Nobel laureate Dennis Gabor created the first hologram in 1947. He discovered the effect while trying to improve the newly invented electron microscope.
True Holograms require a LASER to illuminate the scene, a photographic plate to record the original LASER and the interference pattern created by the scene.
Then you need a LASER to project through the resultant plate and hey presto the original scene is created when the viewer looks through the plate, if the viewer moves their head the scene shifts in true 3D.
These days natural light holograms are available, like your VISA card, though the effect is not a good.
I think the most amazing thing about holograms is that all that is recorded is an interference pattern, what this means is that if the plate is cut in half or even a hole put through it, the entire scene is still present, though at reduced quality.
Could I create my own Pepper's ghost?
You could try!
Here's some videos to get you started...