Drive-by Free Speech
...interesting site where they take pics of signs (all seemingly anti-Bush/war) that have been put on overpasses. This brings me back to one of my strongest beliefs...if you have an opinion EXPRESS IT! Love or hate their message, they are certainly trying to convince others to think about the issues. I personally don't think that what they are doing is effective, short meaningless catch-phrases and pics without any context isn't persusasive in my opinion, but I love the fact that they are trying something. Do you disagree with their views? Tell me. Tell your coworker. Tell your spouse or sibling. Tell someone! Holding your opinion in a void does nothing but gives you an ulcer.
Start a blog, rant at a friend, call into a radio show, write a letter, whatever it takes, but share your opinion. This is a democracy still, so take advantage of the fact that you can say what you want, when you want.