Open Source Filtering?

David Guichard asks: "Maybe I've just missed it, but has there been any talk or action on an open source Internet filter? I'm thinking of something that would allow libraries and schools to comply with the law, but would not hide the list of forbidden sites and would allow complete local control, and certainly would not track user browsing. I realize a lot of people wouldn't want to get anywhere near this on principle, but it seems like a winner to me. For example, would junkbuster satisfy the law already? What is missing that the law requires?" If you have to have some form of filtering in place, better an open solution than a closed one.