Scientists are fickle, aren't they? First they're saying we can't have invisibility cloaks, now they're saying we can. I vote "can," obviously. How will it work? The same way everything in the future will work: nanoparticles.
A team from Fudan University in Shanghai believes that silver-plated nanoparticles suspended in water could be the trick to draping yourself in invisibility:
In the absence of a magnetic field, such nanoparticles would simply float around in the water, but if a field were introduced, the particles would self-assemble into chains whose lengths depend on the strength of the field, and which can also attract one another to form thicker columns.
The chains and columns would lie along the direction of the magnetic field. If they were oriented vertically in a pool of water, light striking the surface would refract negatively – bent in way that no natural material can manage.
This property could be exploited for invisibility devices, directing light around an object so that it appears as if nothing is there, or be put to use in lenses that could capture finer details than any optical microscope.
See, scientists? That wasn't so hard! I hope this is lighting a fire under the asses of the USPS owl-training division. [New Scientist via Slashdot]