If you want drivers to cut you more slack when you're cycling, however, the advice is dress as a woman (if you're not one already, that is):
His findings, published in the March 2007 issue of Accident Analysis & Prevention, state that when Walker wore a helmet drivers typically drove an average of 3.35 inches closer to his bike than when his noggin wasn't covered. But, if he wore a wig of long, brown locks -- appearing to be a woman from behind -- he was granted 2.2 inches more room to ride.