There is about 3000 billion billion bytes worth of digital information in the world 
 
Hard disks are expensive and require a constant supply of electricity 
The best ‘no-power’ archiving materials such as magnetic tape degrade within a decade 
DNA is a robust way to store information 
It is also incredibly small, dense and does not need any power for storage 
Researchers at the European Bioinformatic Institute encoded:  
an mp3 of Martin Luther King's speech 'I Have a Dream'  a .jpeg photo of EBI
a .pdf of Watson and Crick's seminal paper 'Molecular structure of nucleic acids'
a .txt file of all of Shakespeare's sonnets
and a file that describes the encoding
The researches downloaded the files from the Web and used them to synthesise hundreds of thousands of pieces of DNA 
The result looks like a tiny piece of dust
In the right conditions this information will last 10 000 years 
As long as someone knows what the code is it will be possible to read it back if you have a machine that can read DNA Wall piece credits: EMBL-EBI researchers make DNA storage a reality, Nick Goldman press release Jan 2013