So some boffins at University of Arizona have created a new holographic medium that allows the user to write, and more importantly, rewrite a holographic image onto it. If I understand correctly, the material is photoreceptive at 532nm, at which an electrical field is created that changes the refractive index of the material at whatever point got shined on. The material will hold an image for about three hours before losing it. Earlier holographic media relied on a one-way chemical change that, while cool, was permanent. This new technology is something you could have in your home, loading up holographic messages while you’re out (from the Princess, maybe) and relaying them to you via your household R2 unit.
I love the animated GIF at the source story. Too bad that GIF weighs four megabytes.