Maybe you've noticed it before and never given it a second thought. What does the triangle indicator next to the gas tank mean? This feature has been added to virtually all cars since the mid 2000's, but many people still don't realize what it is trying to tell you.This isn't something that will be of much use in your own car, but if you ever rent a car this is a great little tip. Notice that the triangle in the picture above points to the left? That means your gas cap is on the driver's side of the car. And yes, the arrow would point to the right if your gas cap was on the passenger side.

Steve Hix/Thinkstock

According to, an e-mail version of this tip starting circulating in October 2007. That e-mail didn't quite get the story correct. There are also claims that the gas pump icon itself indicates something, but that does not appear to be true at all. Did you already know about this auto secret? Or is this tip news to you?