I think I may have something that will enhance your idle time while sitting in the parking lot waiting. Instead of just sitting there, how about trying this? grab an old cell phone..preferably one that is inactive and dead as a door nail; flip it open, and talk to God.
Let's face it, if you were to talk out loud in an attempt to pray and someone was to watch you, they would consider you to be nuts. This is not a pride issue. all you have to do is to ask yourself the question: "What would I think if I were to see someone carrying on a conversation without a blue tooth in their ear with no one else in the car?" Chances are you would wonder if they were "missing a few marbles". What a great way to be one up on Satan and at the same time keep your testimony in tact (not to mention your brains as would be the case in the eyes of the beholder) This cell phone idea works! I have been carrying on many a conversation without any one having a clue as to who I am really talking to. I recommend it strongly! Don't forget to be quiet and allow God to talk to you.