Physics professors Mikhail Lukin of Harvard and VladanVuletic of MIT have successfully created a scenario where photons of light bond together to create mass, a logically impossible, but scientifically probable outcome.
The two scientists filled a vacuum chamber with rubidium, and then laser cooled the chamber to near absolute zero. This temperature is 0 Kelvin, where the very particles of atoms have no movement, thus rendering the atoms frozen. Lukin and Vuletic fired single photons of light into the atomic cloud of rubidium, which made the photons give off energy to the unmoving rubidium atoms, thus drastically slowing the photons of light.
When two photons of light were fired into the rubidium cloud, they emerged bound together as a molecule. Because of this breakthrough, there is now talking of one day creating 3D crystals out of light itself.
There are nerds, like myself, who see this breakthrough as a scientific milestone toward the eventual creation of lightsabers. A man can dream, right?