This past weekend my car's battery died when I went hiking. I don't think I left any lights on, and there was actually enough power to run the radio or lights, but not enough to get the engine to turn over. Fortunately, it was a popular enough trail that I was able to get a jump from a fellow hiker. Naturally, there was no cell service in the parking lot, although ironically there was if I had hiked about a mile back up the trail.

So now that I'm thinking about places that are a little more out of the way and where I might not encounter other hikers, it's making me wonder what else I should be carrying in my car. Extra food, water, and a blanket in case I have to stay a night in the car, but what else would you recommend?