2 Terabytes (2 million megabytes).
Here's what you can do with 2 TB worth of data. You can store it on this Lacie 2TB hard drive which anyone can put on their desk for about $600.
When the Large Hadron Collider becomes operational next year some of the most important physics experiments ever devised will be carried out. Some really interesting data will be produced there at the annual rate of about 15 Petabytes (15 million million megabytes). This is just from one source. Now imagine all of the ways we will continue to create data. If we extrapolate into the future the growth we've seen thus far it quickly becomes mind boggling to consider where to store it all and how to maintain it so that it doesn't disintegrate and disappear into the ether.