More and more information about us is now online, but now researchers say what's not easily accessible about many of us can be pieced together.
Most of us can go out in public and remain unrecognized, but facial recognition systems may soon allow strangers to snap your pictures and instantly learn your name, your date of birth, where you were born and maybe even your social security number.
"I think facial recognition is probably here to stay," said Jennifer Lynch with the Electronic Frontier Foundation.
Facebook and Google are two companies that are already using some forms of facial recognition. Facebook's "tag suggestions" feature automatically identifies people in photographs as they are uploaded.
A video published by Google shows how owners of the Samsung Galaxy Nexus can unlock their phones simply by pointing it at their own face.
"We're getting closer to the end of anonymity as we know it," said Carnegie Mellon associate professor Alessandro Acquisti.
Acquisti and his fellow researchers at the university have developed an application he says can determine the name and other personal information of a stranger with fairly good accuracy.
Acquisti demonstrated the technology by taking pictures of three subjects and then uploading them to his app. The application spit out information about each of them.
"Yeah, that's my name...that's my date of birth...that's my state of birth," said test participant "Mary."
The app also accurately determined the same information for a test participant named "Paul."
"I'm pretty impressed," said Paul. "But it's also weird. It's kind of scary losing anonymity like this."
The technology works by comparing points on someone's face -- such as their eyes, nose and lips -- with a database of photos compiled from the Internet. Once the subject is identified, the app searches public records for other information.
"People take pictures of you, and they upload them," said Mary. "You have absolutely no control over this, and one of the reasons you think it's kind of OK is 'Well, this picture isn't tagged, there's no way it can come back to me,' but apparently it can."
The app had less success with social security numbers, failing to bring up the numbers of all three test applicants, but in the past, Acquisti said the app had a success rate of 27 percent in predicting the first five digits of the subject's social security number.
That's a significant probability because the remaining four digits are often publicly available.
One the third test subject, the app correctly determined the name and state where subject "Lisa" grew up. That was enough to make her concerned about stalkers.
"Seeing this, I would be afraid of that," Lisa said. "I wouldn't be afraid of that before, but guess I am a little bit now."
Acquisti has not released his app to the public -- he only developed it to prove it could be done. Acquisti predicts facial recognition systems will be widely available and much more accurate in five to 15 years.
The FBI confirms its own facial recognition system is in a pilot program and will be rolled out on a limited basis next year.
"The big risk is that there's a chance that people could end up in the database, and they have absolutely no association to crime at all," said Lynch.
Google Images already has the ability to identify images uploaded onto its website. Could facial recognition be next?
"I think figuring out a way, if there are ways it can be done, that wouldn't violate our user's privacy, it could be considered," said Peter Linsley with Google.
Capitol Hill has already taken notice of facial recognition technology. Senator John Rockefeller has asked the Federal Trade Commission to participate in a workshop on facial recognition technology scheduled by the commission next month.
Both Rockefeller and the Federal Trade Commission declined to talk with ABC7 about this story.