Here are two things that are probably true: you don’t smoke, and you own an old, disused iPhone dock. Here are some things which are almost guaranteed to be true: You own a dock connector cable and a 3.5 mm jack cable
And if you live in the U.S, and you haven’t yet achieved enlightenment and switched to a bike, then you almost certainly have a car. Put these things together and what do you get? Jalopnik’s neat DIY in-car iPhone dock.