IBM develops storage technology that can store up to 250Gb in space of postage stamp

[devolution]

This is really interesting:

http://www.research.ibm.com/resources/news/20020611_millipede.shtml

IBM have created a modern day version of 'punched card' technology which uses near-atom-sized access techniques.
Similar to the CD-RW phase-change technology but on a very much more denser scale, the 'Milipede' wafers can store huge amounts of data.
A wafer the size of a computer base unit could potentially store all the data on every computer in the world with tons to spare.