By now, we US citizens are all very very aware that our metadata is being harvested
Immersion functions with Gmail (and Gmail only) to pull all your historical data about who you're sending emails to, who you are getting them from, who you are CC'ing, and when it all went down. MIT promises to not peek at the subject or the body of those emails while it's in there, and you can delete it all from MIT's servers at your leisure.
The result is a big, beautiful web showing who you talk to and when, just like the big boys have, and you might be surprised at exactly how much it betrays about your everyday life.
Unlike PRISM, Immersion is proving to be pretty popular, so it's somewhat overloaded at the moment. But if you leave your email, MIT will get back to you when it has a spare moment to snoop on you. In the meantime, you'll have to be content knowing someone is collecting all that data, even if you don't get to see it. [MIT via GigaOM]