As if you weren't paranoid enough about your Facebook privacy settings, now your ever social-media move can be mined for the purposes of actual spying. The Guardian has lifted the veil on RIOT, an as-yet-unsold program from defense contractor Raytheon that looks through Facebook, Twitter, Gowalla, and Foursquare to find out where a person lives and hangs out, to discover what he or she looks like, and even to predict what he or she will do in the future. With the secret program — officially named Rapid Information Overlay Technology — it took Raytheon's "principal investigator" ess than a minute to put together this map of where one man travels:

It took another minute to find a picture of the man and an additional minute to discern the best place to find him at 6 a.m. on a Monday morning (his gym) — it's a terrifyingly efficient process, all of which you can see in action in the video below.

As much of a privacy overstep as this appears to be, it's totally legal because we're the ones sharing the information on the public Internet. Just a year ago the FBI put out a call, looking for a "social media alert mapping and analysis application solution," according to a request for information (RFI) posted on FedBizOpps.gov. The United Kingdom has also indicated similar interests. Ratheon hasn't sold the technology to any of its clients, but the world's fifth largest defense contractor said it worked with the U.S. government in 2010 on the Riot project. 

For obvious reasons, privacy experts think the program presents some possible privacy violations.  "Social networking sites are often not transparent about what information is shared and how it is shared," the Electronic Privacy Information Center's Ginger McCall told The Guardian's Ryan Gallagher. "Users may be posting information that they believe will be viewed only by their friends, but instead, it is being viewed by government officials or pulled in by data collection services like the Riot search." With data-mining tools, making people uncomfortable can count as a privacy violation, as we have seen with other oversteps taken by Facebook.

In any case, this might be a good time to ensure those Facebook privacy settings are locked down. If you change your sharing settings from public to custom — or "friends," per the picture at right — that might help keep private contractors off your digital trail. Or, as always, the best way to avoid unwanted tracking is to abstain from Internet sharing altogether.