I've run out of gas once in my life. Luckily, I was only at the gym and a gas station was right around the corner. But my brother made sure to let me hear it on how irresponsible it was to even put myself in position where I could run out of gas. Not only was I embarrassed, but it left an impression on me that has lasted till this day. I will never let that happen again.
Never let your tank get below half was his advice. I've done my best since then to make sure that whenever I get close to half, I fill up. Same goes for my wife. I learned my lesson. It's common sense advice that could be incredibly valuable if you ever need to be on the move quickly and getting gas is unrealistic. Don't be like the younger dumb me, make it a point to top off anytime you get near half a tank.