July 16--When you Google "anti-acne remedies," send a Tweet, sign up for Farmville on Facebook or use Yelp to find the nearest sushi restaurant, you open a digital window into your life.

Those services collect and store reams of this personal data from millions of users, creating a potential gold mine for the companies and advertisers.

But can we trust them to protect our privacy?

"The largest, most-profitable unregulated industry in America is data and data mining," said John A. Curr III, executive director of the Western regional chapter of the New York Civil Liberties Union.

Facebook, Google and Twitter have come under fire in recent months from consumers and privacy advocates, who contend the companies have compromised personal data or made it harder for users to secure.

The privacy breaches are prompting members of Congress and federal officials to consider stricter rules to protect our personal data.

While consumers worry what companies may be doing with their data, these same consumers share vast amounts of intimate information online.

They freely post phone numbers, home addresses, birth dates, photos and other identifying details on Web sites.

"That data lasts forever. It doesn't go away," said Anthony G. Basile, information technology chairman at D'Youville College.

With the growth in GPS technology and mobile devices, users of services such as Foursquare now can reveal their movements to friends, strangers -- and savvy criminals.

These locational services are leading to personalized ads that speak to you from TV screens and coupons that pop up on your mobile device as you walk into a restaurant or store.

But skeptics warn that consumers should weigh how much personal information they give up to get a coupon for a latte.

"Consumers need to be careful about letting marketers have unfettered access to a digital-data Fort Knox of information about them," said Jeffrey Chester, executive director of the Center for Digital Democracy.

Kate Holzemer, a viola player with the Buffalo Philharmonic Orchestra, takes the attitude that anything she writes on Facebook has entered the public domain, even though she keeps her privacy settings high.

"I hold back a lot of information about where I am, if I'm out of town. I never reveal my exact location at any time," said Holzemer, the Kate Bits blogger.

Adrian Roselli regularly posts pictures of the meals he has made or eaten, such as the penne with chicken in vodka sauce he enjoyed Wednesday night at Amici Ristorante & Cafe in Kenmore. But he won't put online a photo of other people unless he has their permission.

When Roselli finds out about a new service, he tests it through a fake account before deciding whether he is comfortable using it under his own name.

And on Facebook, he doesn't say who he is related to or who he is dating, and he doesn't "friend" his family members, all to limit how much people can find out about him.

"You don't have to give up information to participate in the world," said the senior usability engineer at Algonquin Studios.

The information that users post on their profiles can reveal more than they intended.

Two Massachusetts Institute of Technology students developed a software program that predicted with a high degree of accuracy whether a Facebook member was a gay man, a project dubbed "Gaydar," the Boston Globe reported.

And Carnegie Mellon University scientists used social-networking sites to accurately predict the full, nine-digit Social Security numbers for 8.5 percent of the people born in this country between 1988 and 2003, according to the school.

"The more information people have about you, even if it looks innocent, then the more they're going to be able to harm you," D'Youville's Basile said.

Preserving privacy has been an ongoing issue for these services.

In May, Facebook produced a near-mutiny among some members when it introduced a service that automatically gave other Web sites, such as Pandora and Yelp, access to users' personal information.

Fifteen consumer groups filed a complaint with the Federal Trade Commission in response.

A "Quit Facebook Day," set for May 31, persuaded nearly 37,000 people to pledge to leave the site -- but that's a fraction of Facebook's 400 million users.

Sen. Charles E. Schumer, D-N.Y., was one of four senators who wrote a letter to Facebook founder Mark Zuckerberg, urging him to give users "full control" over their personal data.

In June, Facebook launched a privacy page, www.facebook.com/fbprivacy. The company also made it easier for users to block features that give third-party Web sites their personal information.

Google has had its own privacy issues. A class-action suit filed in February alleges that the Google Buzz social-networking service shared personal data without the consent of users.

In June, Google denied violating federal law when its Street View cars picked up data from unsecured Wi-Fi networks.

The FTC and Congress are showing more interest in the issue of online privacy, but the NYCLU's Curr wants to see a "bill of online rights."

Alan Bedenko, the Buffalo Pundit blogger, uses Foursquare to check in at the Whirlpool Bridge, Buffalo City Hall and the Hatch restaurant.

Someone who isn't friends with Bedenko can see basic information, such as his total number of check-ins, his badges and his tip to try the she-crab soup at Black & Blue Steak and Crab.

They can't see where Bedenko is checking in, but Bedenko links his Foursquare updates to his Twitter feed, which is public.

Bedenko said he never checks in at a location where he is dropping off his children, such as their day care center, and he hasn't listed his home address.

But he said he isn't worried if people know where he is, and he doesn't mind if companies have this information.

"I'm not by nature a paranoid person. If they're going to use that information, they're going to use it to market to me. They're not going to use it for something evil," Bedenko said.

Locational data is valuable to advertisers because it gives these firms an unmatched insight into where consumers spend their time and money.

If someone using Foursquare regularly checks in at McDonald's, the chain can send a coupon for a Big Mac to your smart phone, for example.

Or if Banana Republic knows that you shop on its Web site, and it sees that you are visiting Walden Galleria, it can connect the dots and try to lure you into its store with an ad.

But do we really want marketers knowing when we pick up a prescription at a pharmacy or whether we visit adult bookstores?

"Location-based data is a privacy catastrophe waiting to happen," said Peter Eckersley, senior staff technologist with the Electronic Frontier Foundation.

The people who use these sites say they are willing to give up some personal data in exchange for the value of these services and the occasional targeted ad.

It's clear this technology is embedded in our lives today.

Asked if she could give up Facebook, Colleen Callahan paused, laughed and said, "No."

"It becomes part of your connection to people," said Callahan, associate director for Web community and development in the college relations office at Buffalo State College.

swatson@buffnews.com

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