I have read that there are some that are hardy to zone 6. I don't think they can produce fruit though because of the length of the season. I think it will stop traffic!
Here in zone 6 I used to have to dig mine up in the fall, and store the stump in the basement. They are really cool, and now I wouldn't mind getting another one, although when I had them, they were a pain in the rear to take up in the fall. They look really good in a setting with other tropical looking plants, like cannas and hibiscus.
Oh, and the banana plant will produce little plants occasionally from the base that can be separated.
@so lucky Did you plant things around your banana tree, and if so did you dig those up in the fall as well? My husband wanted to decorate around the horse shoe pits (which is what is in the background). I'm more worried about "friendly fire" than the weather at this point.