With all of the recent move to put cartography and GIS data on the internet, it should come as no surprise to readers of this blog that there are a lot of web sites out there with nice looking maps and data that everyone expects to be real. This is where people should stop to think about the source of the data.

A beautiful map is a beautiful thing. And, once upon a time, a nice looking map with data on it was a sign that some dedicated organization had paid a lot of money to create it. Nowadays, that isn't the case. With a few data points and a little code from Google, you can create your own Google Maps mash-ups.

It should come as no surprise that somebody has illustrated this with the web site Felon Spy, a site that advertises itself as showing you the locations of dangerous people in your neighborhood. In truth, it's a ruse. Randomly generated "perps" are placed on the maps near whatever address you choose.

As with PhotoShop and photographic "evidence", these mash-ups should give the public pause when looking at maps online.