I find it interesting that there seems to be a cultural difference in regards to the word ma'am. Where I am from, (Ottawa, Ontario) it is considered rude to call someone ma'am unless they are visibly over the age of 50. A lot of younger people would get scolded at high school jobs for calling a woman ma'am. The proper term to use is miss. I was also watchin a television show last night, where the woman was in her late 30's and she started to feel old because a younger man called her ma'am. This was in Seattle, I think? I've seen it in a show that took place in Boston as well.
Here in upstate South Carolina however, it is common to call everyone ma'am and considered polite, no matter what the age. I have been called ma'am on many occasions, and I find it amusing, since I'm obviously young and I know it isn't reserved for only older women as it is where I am from.
Which way is ma'am used or interpreted as where you're from? Any other words come to mind with this kind of effect?