Google Maps Mashups are a joy to use. You can now find out your ex’s location just by typing in the first 6 digits of the 10 digit phone number in the US/Canada.
NPA-NXX Geolocator shows you the location in Google Maps as soon as you type in the 6 digits. It could not locate my cell phone number which is probably quite normal but it accurately found my town.
There are other ways to find this information but who could resist looking at a Google Map mashup?