Question: You're handed a 10GB flash drive and told, "We're closing down the internet, what do you want to keep?". You have one day to fill the space and connection speed is not a limiting factor. What do you put on your drive?"
Question is from Reddit, courtesy of Jaime C.
So, the question is clearly a bit infeasible, but raises a few good points. I'll address this from multiple perspectives.
Personal monetary gain
The internet is being shutdown, so what does everyone else want which they can't get anymore? The internet is used for gaming, informating finding, fact checking, and much else. But if you look at the average techie user, what do they do the most? Browse Reddit and 4chan. I'd download Reddit and the 4chan archives. 4chan might be a bit big, but perhaps people can live with little, 64x64 gif images. I'd write some application to start Reddit back at day 0, with people posting and commenting based on the dates of the posts. Browsing locally, it'd feel just like 2005 again! You could even make yourself a user and wait for other people to comment on your posts, inserting them where others had before. You could post anything you like and have people upvote you. It'd be really something, any geek's dream. All for the low cost of a year's worth of internet access, back when the internet was around. For sale on a flash drive. "Buy the Internet! As seen on TV!"
So the internet is being shutdown tomorrow. You know what's really, really valuable? Personal information. I'd probably download a large portion of Google Street Maps views and Facebook personal information data. Stripping out needless HTML and such, of course. Compressing the text with xz. The internet is the #1 utility for stalking people, and I'd have all that information when others did do not.
So what do I personally want from the internet? There's two ways I'll go with this.
A. Things to bring the internet back online. I'd download all of the RFCs, ISOs of NetBSD (with source code), Linux kernel source tarballs, all my favorite patches, and whatever else I can find. I'd get every useful ISO, documentation, and code for managing the pesky PC hardware we're all stuck with. Definitely some x86 opcode charts, assembly books, and whatever else I can. I'd use this information to reconstruct the internet. Except, once taken down, the internet is no longer the Internet. This would be the TeraNet.
B. Internet is staying off, what do I really want to keep? Probably a few things on Forth and assembly. Then I'd mirror texts relevant to my interests. Motorcycle and car forums. Survivalist information. Lockpicking ebooks. Evasion techniques. I'd take screenshots of all of my websites as mementos. I'd also fill it up with maps, maybe things to print off. Constitution, too. Also a readme on the internet, explaining how it was shutdown and such, in case it was discovered years later.
So the internet is going offline tomororow? It's going to cause worldwide panic. You know that thing called Facebook? Every fourteen year old is addicted to it, and communicates through it almost as much as texting. Businesses all depend on the internet. Without it in the present world, everything would crash. Businesses, customer traffic, money exchange, flight purchases, just about everything. Even if you weren't affected, things and people along the way would be. This would be an all out apocalypse. People would be out of jobs. Companies wouldn't be getting purchases, and would close. The USD might crash. This would be somewhat like a zombie apocalypse.
So to be frank, while I'd save every bit of data possible on that 10GB memory stick, I'd be much more concerned about my own personal safety and that of others. Bullets, guns, bullion, and reliable transportation will be in much greater demand than every before. And the payment? Probably threat of death. People just trying to save their families, friends, and themselves. I'd stock up on survival essentials and probably leave to farm towns. The cities would be a scary mess.
Fortunately, shutting down the internet is not easily feasible. It's not very centralized, and it's hard to restrict. While it would be easy to put up mini-internets if the real "internet" was somehow shutdown, everything would still fall over on its face. The biggest immediate (not necessarily long term) risk of losing the internet is the stopping of commerce, which controls the flow of just about everything. The next biggest risk is centralization of information and control of people. 1984 might be that much more of a reality (not that it isn't, already!).