The map gives information on 274 Internet exchanges and 512 buildings. Click a specific pin to find out more information about that exchange. It's interesting to see how concentrated these high-tech spots are in Europe for example, yet how sparse they are in Northern Africa. If you wanted to destroy the entire online world, this map would be a good starting point. [InternetExchangeMap via Telegeography, h/t @ajblum]
Hmm. The Philadelphia site must be super top-secret....they don't even list the address.
I could tell you where it actually is, but then I'd have to kill you. I'll give you a hint though.... its a big ugly hunk of a building. The kind that, if you looked at it, you would say "there's nothing important that could possibly be in that building."
PS- its not top secret.