If you own an OnStar-equipped GM vehicle and drive less than 15,000 miles a year, you may be able to save as much as 54 percent on your car insurance. Thanks to a partnership between OnStar and GMAC Insurance, drivers can participate in the OnStar-GMAC Low Mileage Insurance Program -- a unique GM feature that tracks your mileage and forwards the data to your insurance company via email. Depending a number of miles driven, subscribers can save $1,500 to $2,500 on monthly premiums. All you have to do is opt in and give OnStar permission to share your odometer reading with the insurance company. For more check out this video or learn about pay-as-you-go insurance and related privacy concerns here.