Cars driving to fast on the streets

Cars driving to fast on the streets :

All that we can do is look and shake our heads because stop signs do not even work.I would suggest
driving every day but keeping to the speed limit will show a good example and then spread the word through word of mouth.Some way it will reach to those drivers.Also with our modern technology these days they should sell cars with a monoter that tells if they have driven over the speed limit,and it must send their details through to the traffic department if they do.