Linkspam: How geomapping IP addresses can make people's lives hell

How Cartographers for the U.S. Military Inadvertently Created a House of Horrors in South Africa

TLDR:  the US National Geospatial Information Agency mapped Pretoria to someone's backyard, companies that run databases that geolocate IP addresses (which turns out to be a startlingly amateur process) then mapped every Pretoria IP address (over a million) to that backyard. Any time a crime or online dispute got linked to a Pretoria IP address, the database threw out that backyard, but didn't mention the small print.. Harrassment happened, including having the house stormed by SWAT.