Marlboro Men: Helena, Montana, banned smoking in public places for six months and saw a decrease in heart attack admissions. There were 16 fewer heart attacks in the region that serves 68,000 people during the six months of the ban. (The study is here in pdf form.) That's a very small difference, and could be accounted for by just about anything - from fluctuations in population size to other illnesses such as respiratory infections that might have been circulating in the community. But expect it to be used to support more public smoking bans.