Avis, the global car rental company is testing an RFID technology that will enable it to keep 5,000 of its cars at the parking lots of client businesses. Clients will be able to use a PIN with their mobile devices and pick up a car kept on their own premises.

Avis teamed up with RFID manufacturer I.D. Systems of New Jersey to launch the technology and will roll out the service in the US and Canada next month.

To use the service, a rental customer visits Avis' website and reserves a vehicle. The customer gets the PIN, finds the car in the lot, unlocks it and drives away. The RFID locators will track rental gas consumption and other vehicle microdata. On return, all the information Avis needs is transmitted back to the website by the tracker.

The device itself is a type of radio transmitter that looks like something the Ghostbusters would use. It has two Wi-Fi router-like antennae and a black box with dials on it.

This move marks a change in the way rental companies do business. It's a lot like ZipCar, which enables a customer to pick up the nearest rental car in any neighborhood in their city. Several mainstream rental companies have already made it possible to pick up cars on the street in major cities like Los Angeles and New York.

For those worried about the Big Brother-ification of their rental behavior, it's not uncommon for rental companies to track their cars. It's normally seen as a type of security measure and for the customer's safety. If the car breaks down, it's easier to find the broken vehicle and send help.