While working on my proposal for the Presentation Zen book this weekend I spent some time going through all the archives of the PZ site. I came across this post I wrote back in September, 2005 on finding design inspiration from ads inside Japanese commuter trains. The posters from Japan Tobacco on the "Smokers' Style" campaign are still a very interesting example of mixing text, simple graphics and simple color to get a message across in a sea of clutter. Take some time to go through the posters. You can see each poster in a larger size here and even get a pdf version of each poster.
See many more posters from the series here.
I love the posters in a weird sort of way which I can't quite explain, and they were remarkable while they were displayed in public over a year ago. However, I don't think they did anything at all to improve the habits/manners of smokers in Japan.
NOTE: The "Smokers' Style" campaign was not an anti-smoking campaign; it was a "manners" campaign sponsored by (ahem) Japan Tobacco. If you are interested in the anti-smoking movement in Japan (such as it is), there is some info in English here. In 2002 the Health Promotion Law (Article 25) was enacted to protect people (employees and customers, etc.) from passive smoke in public buildings, restaurants, etc. The problem is establishments currently only have the "duty to endeavor to take necessary measures to protect users." Much more info about the Health Promotion Law and the protection of non-smokers in Japan here, and here in Japanese.