4.2mi night commute, 5 lane 45mph arterials. Night traffic isn't as busy but tends to move faster than posted limits. When I first started last summer I rode the sidewalks all the way to work. I knew that winter would make the sidewalks impossible so I gradually worked more street riding into my commute. By the time I started riding the streets I had most of my safety gear: headlight, blinkie, safety vest, helmet. Like DataJunkie, I would prefer to stay off the arterials but that isn't an option for 3/4 of my route.