In these days of the 24/7 news channels, it's hard to believe that there might be some things that we don't know about the presidental candidates. Just in case Chris Matthews, Wolf Blitzer and the rest of the pundits may have missed something, the following are books either about or by one of the politicians in the 2008 presidential campaign -- Hillary Clinton, Mike Huckabee, John McCain and Barack Obama. And, as of this past Sunday, add Ralph Nader to the list!