The miracle of global positioning systems is going to let parents know when their child is late for curfew, plays hooky or sneaks out of the house at night. And the 24-hour-a day service is going to cost just $200 a year.

Vince Poloniato, president of Track 'Em, has turned his attention to capitalizing on parents' need to keep a close watch on their children or anyone else.

Poloniato began marketing the service three years ago to employers as a way of keeping track of staff taking long lunches or using company vehicles outside of work. But over the past year, an increasing number of parents have been ordering the service and his clientele has grown to 3,000, he said.

The tracking device, which can be planted in vehicles or accessed through cellphones with GPS service, allows the user to pinpoint the exact location of a person by logging into the company's website.

The location can be displayed on a map or by address and information is updated every two minutes.

The user can view a timeline of where the person has been all day and even access a history of where the person has been months earlier.

The user can also set "fences'' around certain locations, which enables them to be notified when the person they are monitoring crosses over the line.

This service is especially useful for parents, said Poloniato, who uses his service to track his 17-year-old son, his wife and his employees.

"If my son doesn't cross the fence around our house by 11 p.m., I will know about it,'' he said.