Spam was once a simple annoyance. But its exponential growth — reports suggest that about 90 percent of all e-mail is spam — has led e-mail users to build daunting ramparts to block unwanted messages and companies to circulate blacklists of alleged spammers. One cannot fault people for seeking ways to avoid unwanted or aggressive solicitations, but the consequences of some anti-spam measures may not be what the people seeking protection from spam had in mind. Some efforts to block unwanted e-messages are threatening free speech on the Internet.
Souce: Washington Post
