Well, the rate hard drive sizes have been increasing, you never know. But there’s a serious question there, just what is the size (approx) of everything on the Internet?
http://www.sims.berkeley.edu/research/projects/how-much-info/internet.html
terabyte=1000 gigabytes there bouts.
Since the “Web” is only a small part of the “Net”, one could assume that all the data on every computer which is “hackable” is thus “on the 'Net”. So, add up the capacities of all the hard drives on all the computers on the Internet, and there you have it. 
One wonders why you ask - did your boss (visions of pointy-haired Dilbert boss) ask you to make him a local cached copy so he could surf faster?
AmbushBug
I think this is what Google is trying to do (Man, they must go through some HDD storage).
Only 7.5 exabytes? Sweet! Lessee, I’d need 46,875 120-gig hard drives to hold that all. At $133 apiece, that means… I can store the entire Internet locally for less than $6.3 million! Sweet!
The information in that link is circa 1999 and is now three years out of date and given that the web has been growing by approximtley 100% + annually and given the amount of audio/video stuff currently available on the web I think the stated 14k per page average estimate is an absurdly small figure and that the 7500 terabytes projection to contain the current world wide web is off by at least an order of magnitude.
This website gives a great history of the internet. All the way down the page, they give a few nice graphs on the growth of the internet. Every 1-2 years it’s been growing 1000%.
Right now I’d estimate there to be at 40 million websites, 160 million hosts, and, well, a lot of internet.
How much? I dunno. There are a lot of people on this site. Maybe we could all divide it all up into portions and each take a share to DL onto our computer. If it fits, we have an answer.
The “net” or the “web”?
if you mean the “net” that means everything on Kazaa, FTP, HTTP, public access databases, telnet etc.
I know that quite a few multi terabyte databases exist in corners of the web, stuff like climate reasarch with 30MB pictures and stuff.
I’m not sure I could explain the difference. I use the terms synonymously (probably in error). What is the difference?
The “web” means every document publicly accessible using HTTP.
The “net” includes every computer physically connected to the internet, whether or not it is running a web server. For example, AIM and IRC are part of the net, but not part of the web (even though they are somewhat integrated)
Slight hijack, where are these 7,500 terabytes of info stored? If there a big supercomputer or something? If not where is it? If its nowhere then how are we storing information on it?
It’s not nowhere. It’s everywhere. My webpage, for instance, is stored on a web server down the hall, under the physics department sysadmin’s desk. This message board is stored on a server somewhere in the Chicago Reader’s offices in Chicago. Some things are stored on huge supercomputers, at NASA or the Department of Defense, or the National Weather Service, or any other place that has big computers. Some of it is stored at the offices of various regional ISPs.
hrm… technically, it is impossible to store all the bits of traffic on the net. You can get to 99% or better but not 100%.
reason is that to retrieve the data to store it on your system will cause more data to be created and a never ending cycle. this is not really a problem when working in small networks, but not when it is so big.
am I right?