Depending on the weather and where I am at I will sometime hit the sidewalk on my commute, however when I am on the sidewalk I am much more observant to pedestrians, slowing way down and excusing myself when I pass them (not buzzing them). Also I pretty much come to a complete stop for every road I half to cross. When it's wet out I just don't feel comfortable sharing the road with the cars, I have seen too many accidents when it's wet out. When bike lanes are present I always ride on them which is about 3 quarters of my ride.