After the purchase of his new car and being somewhat paranoid its' location, Jayvis Vineet Gonsalves has devised a relatively simple GPS tracking device that can be interrogated by mobile phone using SMS text messages. The device is simply a combination of an Arduino board, a GPS module and a GSM shield - with an external power supply.
To retrieve the current coordinates of the car, one simply sends an SMS to the telephone number of the SIM in the unit, and it will response with an SMS containing the position data which can then be fed into an online mapping service to determine the current location of the car. For an interesting look at the system, watch the following video:
This project could also be modified to work in other types of vehicles, or send position data or alerts upon the car being stolen or another event. To learn more about this project and make your own, visit Jayvis' Instructable. And for more, we're on twitter and Google+, so follow us for news and product updates as well.