Transportation Alternatives have produced this Google Maps mashup to show pedestrian and biking accidents in New York. The map shows DMV accident statistics so that you can quickly identify which NYC intersections are the most dangerous.
The map includes a slider time-line so that it is possible to view the accidents for any period between 1995 and 2005. It is also possible to select from four different data sets, 'Pedestrian Injuries', 'Pedestrian Fatalities', 'Bicycle Injuries' and 'Bicycle Fatalities'.
Mapping Swiss road fatalities - a map of traffic accidents in Switzerland.
Gothamist Incident Map - plots the locations of crimes, fires, accidents and other "incidents" in New York City