I complained for years about a dangerous intersection. Said intersection has a crosswalk on one side but motorists who need to turn right through the crosswalk don't bother stopping when pedestrians/ bicyclists have the right of way. After about 10 phone calls to figure out who's responsible for maintaining the intersection (it's a state highway and also the boundary between two cities) I found someone at the state dot who got a " yield to pedestrians" sign put up for me. Now drivers actually stop for me when I have the right of way.
(Note: I do ride with traffic going to work but coming home I take that crosswalk. Evening rush hour traffic is heavy enough that I feel unsafe riding on the road.)
I've also managed to convince my coworkers that I can bike to work safely...after three years of doing it.