IF you like this kind of numbers, a few months ago an interview on the Wayback Machine was published, with some ideas of archiving all web pages, music etc

" (...) So if all books are 20 TBs, and 20 TBs are $80,000, that's the Library of Congress. Then something big has changed. All music? It's tiny. It looks like there're only one million records that have been produced over the last century. That's tiny. All movies? All theatrical releases have been estimated at 100,000, and most of those from India. If you take all the rest of ephemeral films, that's on the order of a couple hundred thousand. It's just not that big. It allows you to start thinking about the whole thing (...)"