Just in case you have more than one Tesla Motors vehicle, the Tesla iPhone app can help you keep track of where they are. It can also tell you how much of a charge it has, honk the horn or change the temperature in the car.
Here Monika Kozdrowiecka, owner of two Teslas, shows Peter Cheney of Globe Drive how to access a Tesla via iPhone.
(apologies, but I can no longer retrieve the video – but it was cool. Monika could actually see where BOTH of her Teslas were …)