Octane ratings refer to the stability of fuel, and dictate at which pressures the fuel will spontaneously combust. Engine knocking can happen when the octane rating is too low, resulting in pinging ...

The iPhone 3GS is like a Formula One car: fast, sleek and a thrill to drive. And then, every hour or so, it has to hit the pits to refuel (only, unlike refueling an F1 car, it takes hours, not seconds ...