The Internet is more than just a series of tubes, but how many people can actually describe the physical structure of the networks we use every day? Andrew Blum argues in "Tunisia, Egypt, and Miami: The Importance of Internet Choke Points" that the hubs that connect this "network of networks" are incredibly vital, and vulnerable, whether located in Egypt or the U.S.
steve: This is great stuff. I work in a datacenter, and one of our favorite interview questions is: "Describe how the internet works... but describe it to me like I'm your grandmother". It's a ruthlessly cruel question for a group interview, but it helps weed out the people who memorized some switch and router commands to pass the CCNP or Juniper test, and leaves you with the people who actually "get it".