If you run on the roads, what do you need to do to avoid running accidents?

I just got back from a 6 mile training run and noticed that, despite the recession, the traffic seems to keep increasing. I am aware of two fatal accidents to runners in the past year, caused by vehicles whose drivers evidently did not see the runners until too late. The most dangerous time to run is when the light is just changing (at twilight) to or from dark: this is the time when it is most difficult for a dri...