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The badge screen on the Foursquare app displays the ranks you've earned through various check-ins. - 

One of the biggest trends online is geolocation. Letting your computer or phone report where you are. It's like a physical status update. Your friends get to know where you are, where you like to go, you might get discounts or special offers for going to certain businesses a lot. In return, tech companies get valuable data about where people are going. Foursquare is a location based social networking site that is having big growth. Twitter is incorporating geolocation functions. A lot of people think Facebook is about to dive in in a big way, and bring this idea to its nearly 500 million members. So if you haven't run across this already, you will. You're going to be asked more often to share information about where you are.

Thing is, the law governing who can get the information you share and what they can do with it is 24 years old. The Electronic Communications Privacy Act was passed in 1986, before any of us were online. Today in Washington, a House Subcommittee hears testimony and proposed changes to that law. We talk to Marc Zwillinger about all this. He's a Washington lawyer who specializes in internet practices and privacy issues and he'll be offering testimony to Congress.

We also check in with Alissa Cooper, Chief Computer Scientist at the Center for Democracy and Technology. She co-chairs the Geographic Location/Privacy working group within the Internet Engineering Task Force.