Don't look now, but your life is for sale.
In fact, chances are, your most private information has already been sold, countless times, and you don't even know it.
"When you go on the internet, even if you do it from the privacy of your own home, it's like you're going on the street," says Prof. Jacob Furst at DePaul University. "You're talking about going on the street, leaving notes all over the place, slips of paper, with your birthdate, your name, you favorite color."
Many Americans believe that when they are sitting in the comfort of their own homes, as long as they are careful about entering financial or medical information through encrypted websites, they can reasonably expect that their most private information will not be compromised. But the experts say that's far from true.
"Your darkest secrets? If you put them on the internet, they're in a public space."
Part of the problem is the web you don't see. A software company called "Disconnect" offers a browser add-on which shows you the external sites which penetrate every web page, seeking your data. And if you so choose, it will block those sites.
Fire up Disconnect, and you'll see a galaxy of rotating orbs, often dozens on each page. Experts say that even if you don't consciously leave personal information on a site, that just by visiting, you've left your IP address, computer make, and software version, along with a reasonable estimation of your physical location. Other algorithms are designed to take that kind of information, and seek out other sites where you have enrolled your name and actual address.
"It's there. You as a consumer have already volunteered that information," says privacy expert Panagiota Kelali at Chicago's John Marshall Law School. "Whatever you look for, by using a search engine or anything like that, will be traced and stored someplace, by someone."
"It's absolutely legal," she says. "It's a tradeoff. Privacy, for convenience."
And it doesn't go away -- even if you cancel your membership on a site, reset your browser, or kill the cookies which companies leave behind on your computer.
There are companies which specialize in very specific information. Exact Data of Chicago prepares mailing lists, which it boasts are highly accurate. Everything from brides-to-be, to gamblers, to individuals interested in pornography.
NBC 5 Investigates bought three lists from Exact Data -- Individuals interested in weight loss, pornography, and information on erectile dysfunction. The 7,500 names, complete with addresses and e-mails, cost just $550.
"I have a problem, which I have tried to find solutions to," said one man, whose name was on the erectile dysfunction list. "I was interested, and had been advised to look at some sites, and I did."
That man, who asked not to be identified, said while he was taken aback that his private information was so public, maybe he shouldn't be so surprised after all.
"We don't always think of the consequences of filling out a form or filling out something when we're looking at a website," he said. "I think the notion of privacy has changed dramatically."
Indeed, Furst, the DePaul computer expert, notes that many sites simply sell the data which you volunteer when you fill out a form. For some companies, such data is just as lucrative as the "real" products they sell.