California Tracks Everyone Using Toll Transponders
obtuse writes "Direct monitoring of traffic sounds pretty cool, but some people don't want their toll transponders tracked. They aren't installing direct driver tracking for law enforcement now, but the collected data could be subpoenaed. Of course, anyone who didn't want to be tracked could just put it in the glovebox anyway, so they won't be catching clever felons or tracking real paranoiacs."
In fact, France almost completely relies on correlating the times between toll stations to catch speeders. It's why when you're driving in France you see a lot of people with flashy cars at the side of the road eating lunch or talking for a bit just outside of the toll stations. =)