Here's a rough translation of the Japanese description by me:
"PlaceEngine allows Wi-Fi equipped machines to be able to deduce their current location in a simple way using the connection information provided by nearby services. Machines equipped with Wi-Fi but without GPS can simply obtain their current location. Because it uses electronic information from access points, it can get the current location at places where GPS can't work, such as indoors or underground cities."

It seems like this software can deduce a Wifi-equipped machine's global position like GPS, but without GPS. The website doesn't seem to have English, but the software does.

Unless this thing gets an english description, I will have to delete it from iusethis.