There are several declarations of independence which are actually kind of important, as opposed to the ones which were mere formalities.
- The American Declaration of Independence is by far the most well-known, and for good reason. It drew on no precedent, no old list of dead men demonstrating the truth and legality of their position: it boldly made its own way in the world with plain, readable language, appealing only to common sense. It set the tone for the rest of American history.
- The American Intellectual Declaration of Independence (commonly, "The American Scholar") rebuked those who would continue to live like Englishmen in the United States and retread the countless steps of Europe over and over in the classroom and in scholarship. Unfortunately, due to its rambling it did not have as lasting a hold on the public, but it did create an American revolution for a time, known as Transcendentalism.
- A Declaration of the Independence of Cyberspace, not the declaration but just an individual guy speaking his mind. Unfortunately, see How the Web was Lost for details of the failure of this experiment. However, he did set precedent for the concepts people generally regard as their right on the Internet.