If you've ever received a cease and desist letter regarding something you've done on a Web site, you might want to check out Chilling Effects. It's a nifty site, forged of a collaboration between the Electronic Frontier Foundation and various law school clinics. Its purpose is to
help you understand the protections that the First Amendment and intellectual property laws give to your online activities….Anecdotal evidence suggests that some individuals and corporations are using intellectual property and other laws to silence other online users. Chilling Effects encourages respect for intellectual property law, while frowning on its misuse to "chill" legitimate activity.
The website offers background material and explanations of the law for people whose websites deal with topics such as Fan Fiction, Copyright, Domain Names and Trademarks, Anonymous Speech, and Defamation.