MIT has created a visualization tool called Immersion that helps you understand how the NSA figures out your relationships based on your email correspondence.
We know from testimony and court documents that the NSA broadly collects so called “meta data” from US citizens’ phone calls and email conversations. MIT has created a visualization tools that allows you to see how the NSA analyzes your email correspondence; specifically by looking at the recipients and frequency of correspondences.
You can link your Gmail account to the MIT tool, “Immersion”, here. There are two immediately apparent pieces of information that can be gathered from the tool: The existence of groups, and the leader of those groups within your contacts. It can also reveal “secret” relationships: correspondences with someone that take place frequently, but don’t involve any other of your contacts.
Many people may have been relieved when they discovered that the NSA was collecting meta data (like frequency of correspondence), but not intercepting the content of emails. Other people however, have been claiming that meta data arguably is even more invasive than analyzing the content of emails. This visualization certainly demonstrates how much information you can gather from the seemingly impersonal metadata. Of course, knowing the NSA, there’s no guarantee they aren’t collecting content as well, without us knowing about it.