http://www.time.com/time/nation/article/0,8599,2013150,00.html
From the article:
Government agents can sneak onto your property in the middle of the night, put a GPS device on the bottom of your car and keep track of everywhere you go. This doesn’t violate your Fourth Amendment
Continue reading about TIME: The Government Can Use GPS to Track Your Moves
From the article:
The cameras, which combine number plate reading technology with a global positioning satellite receiver, are similar to those used in roadworks.
So, GPS combined with the plate reading technology could essentially be used to watch you
Continue reading about Telegraph: New Speed Cameras Trap Motorists From Space