I can't believe I've never posted this idea. It always works. Next time you're out of town, ask someone (at a gas station, hotel, restaurant or wherever you happen to be) what the church scene is like in that city. whether they're a believer or not that will instantly begin a conversation about Christianity which can easily be transitioned back to the gospel. I just did this driving to Denver last week and had a GREAT conversation with a guy named David and we even got to pray together! Hope you get a chance to try it out! have a great day!