This post really has little to do with money. But you might save a few cents in gas by not waiting with your car running.
How many times have you been with a person in there car and they spend 10 minutes to find a closer parking spot at the mall? Avoid this at all cost simply park your car far from other people. Not only will you instantly get a parking spot but you avoid dings since your car will be alone and you get more exercise walking to the store. Win Win Win situation!