No, we're not talking wiretapping here--just pure pestering from websites that require you register before using certain features, such as e-mailing a story (e.g. the New York Times online edition). But privacy lovers--and lazy people who hate the hassle of registering--can rejoice, because now there's Bugmenot.com. This site shares logins and passwords that you can use to bypass giving your contact info to everyone.
For example, I just read an article from the NYTimes* and wanted to e-mail it to a co-worker, but didn't feel like registering w/ them, so I looked up the most successfully used login/password combo of siemens2/siemens and got in just fine.
*If you're curious, the article was "Meet the Life Hackers."