Something very similar to this actually happened to an older woman who lives in my condo complex.

She was walking her dog across a driveway to a school when someone sped out of the school parking lot, hitting her. She was not run over, but her arm and a couple ribs were broken. The car knocked her into the street and she said that she laid there long enough for half a dozen cars to pass by. She said that they had to actually swerve around her. The weirdest part was she said that a group of bicyclists passed her and she said that she heard one of them say, "I think this lady's hurt," and another one said, "C'mon," and they rode off.

When I heard my complex lady's story I lost faith in humanity for about a month and now I've lost it all over again!