If you have a teenaged driver and you're worried about them developing bad habits, such as speeding or not using seat belts, there's a technological nanny you can use. The Tiwi is a small radio-connected box that not only records the driver's actions, but it also reports them in real-time. Additionally, you can set alerts for when the vehicle enters or leaves certain geographic areas. At $300 for the box, plus $40 a month for the service, it's not an inexpensive guardian. But there do seem to be a lot of features, including roadside assistance, that might help you justify the cost.