A Lower Hutt family had a series of concrete blocks placed on the berm outside their house after two cars ploughed through their fence after failing to take the corner. Now it appears that they have some vindication for their action - click through to this article.
Although there may be liability issues. Some commentators say that if there was, say, a death in a vehicle due to the new defences, then charges could be laid by police. I hope that a solution can be found that protects both the family and people in vehicles, but meanwhile, I guess I can be grateful that most risk management choices are not win/lose, and risks and benefits can be found for all participants.