14: Improves your math skills. Calculating the optimum mixture based on temperature, humidity, and planetary alignment takes some pretty advanced stuff!
LOL, someone should start a "Advantages of Nitro" thread with all these on there.
And an amended #9:
9: Carrying around the starter box, glow plugs, extra fuel, batteries for the receiver, batteries for the starter, and an extra gallons of fuel will get you stronger as well...good for your muscles and cardio... And if you choose to forego the starter box, the purist route of repeatedly yanking on that pullstring a billion times will also strengthen your arms. Just be sure to switch sides once in a while to maintain an even muscle tone.