If you are teaching a journalism course about blogs, or using blogs,  you may find this list by Jay Rosen, a journalism professor at NYU helpful. It is an initital list of blog postings (with links) that have revealed information that served the public good before the information appeared in the mainstream media. He has invited others to send in other examples to make the list more complete. It is all part of his response to a column in the LATimes about how blogs are useless and unreliable.