4. iPhone or iPod Touch
Need a quick hit of motivation? Download a motivational fitness app directly into your iPhone. Excuses are no longer an option when all you have to do is look down at your phone and suddenly you are infused with the perfect mantra made specifically to motivate you to work out. You can also write your own reminders, list your goals, and create an emergency letter-to-self to read whenever you're on the brink of skipping your workout.