Rather than picking up that new best seller in written form, download the audio version and load it onto your iPod or other device. Limit yourself to only listening to the book while you are running. Once you get caught up in the story, you will want to head out for a run just to find out what happens next!
If you don't already subscribe to podcasts through iTunes, consider starting to listen to some as a way to engage your mind during runs. This is a great option for someone who likes to multitask and lets you keep up on news or other events while getting your daily exercise done.