Israeli company Mempile announced it has successfully created a system to make 1 terabyte optical discs which they call ‘TeraDiscs’.  It has 200 physical layers of about 5GB each on this disc.

A Mempile disc contains light sensitive molecules (chromophores) capable of switching between two distinct states upon the application of light.  This provides for true three-dimensional accessing of small volumes within the material, allowing the writing of data bits selectively within the bulk of the material.

The technology is currently limited to WORM (Write Once, Read Many).