500 gigabytes on a blu-ray disk!

Can you imagine that one blu-ray disk can replace your hard disk drive!
Pioneer will produce soon a blu-ray disk that can store up to 500 GB of data.
It consists of 20 layers and that makes it possible to store such huge amount of data on one disk,but it isn't an easy process as they must be sure that the information written on any layer, doesn't overlaps with
the information on the other layers.I think when this disk is released,
it will make great changes in all storage devices and in the world of entertainment.