Nort sure about this one...

["Ian Lowe" <ian@xxxxxxxxxxxxxxxxxx>]

I'm sure there's some application for HA, but there are a dozen more for
scary stalker like behaviour...

Get your mobile, key in as a text message:

try mapamobile

send it to 83118

A few seconds later, you get an SMS message with your current location,
to within a kilometre or so.

The actual service being demonstrated (www.mapamobile.com) allows you to
track up to ten mobiles (with their consent) at once...

Ian