In the summer 2004 the theme park Legoland in Denmark launched a child-tracking service in collaboration with the insurance company TRYG.

The Kidspotter kit - which is available for rent - consists of a small wristband with a tiny RFID/WI-FI sender, plus a special Kidspotter map of the park.

The wristband is placed on the child's arm and if the parents lose sight of the little creature they can send an SMS message to the Kidspotter system. They will automatically receive a return message stating the name of the park area and the map coordinate of their child's position in the park with an accuracy of 3 meters. On the special Kidspotter map of the park, parents can see where to find their child.

The service is developed by kidspotter.com.

• www.kidspotter.com