Adam Gaffin has created the newest crime map for a U.S. city. He has created a tool which plots on a Google Map where violent crimes across Boston has taken place.
Here is more about his experience in creating the map:
But first, a rant about my beloved home: Boston must be the absolute WORST city in America in which to try something like this, because it's really an amalgamation of old swallowed-up towns, none of which changed their street names when they were annexed, so you wind up not just with three Washington streets but three 60 Washington streets, making it incredibly time consuming to find the longitude and latitude where things happened. I fed 500+ violent-crime addresses into Yahoo's mapping API (congrats to Yahoo for exposing it!) - I didn't keep track of how many of the coordinates came back wrong but I spent a good part of last weekend looking things up by hand on geocoder.us (the data I got from the Boston PD lists precincts where the crimes occurred, but not Zip codes, so at least I was able to figure out when a crime was committed in the South End, rather than Dorchester and then use that information to select from the three or four options presented by geocoder.us, ugh).
More Google Maps Crime Maps: