Netropolitan :

The right to privacy on the Net is rapidly becoming a sensitive political
issue in the US. The Center for Democracy and Technology is an American
nonprofit-making organisation concerned with protecting people’s rights online.
Part of its Web site covers the issue of online privacy (http://www.cdt.org/
privacy/contents.html) and features an interactive demonstration that shows how
much information you are sending to other people. It also links to the
Anonymizer (http://www.anonymizer.com), allows you to surf the Internet without
revealing anything about yourself to others—though it works very
slowly.