From Wired "Cops Test Cannon That Fires Sticky GPS Beacons at Fleeing Cars":

The gizmo, called the StarChase Pursuit Management System, fires sticky GPS transmitters from compressed-air cannons mounted in the front grill of a police cruiser. A backlit control panel allows officers to arm the capsule and launch it at their target; once the projectile is attached to the fleeing vehicle, it starts feeding real-time location data to police HQ over a cellular network. This lets cops fall back and tail the suspect covertly, avoiding dangerous chases.

So utterly Batman.