If the car has come in from racing and idling nicely, I'll just tap it with the side of my thumb and she'll stop without injury, if I am out marshalling and a car is screaming its guts out, I'll flip it over and stop the flywheel with the toe of my boot. I always wear my old (but in top condition) steal cap firefighters boots and the sole at the toe has an edge that fits nicely up to the flywheel and has a hardened, oil and heat resistant sole. The bonus is that they have saved my ankles a couple of times when drivers have got well out of shape while I have been marshalling. I barely felt a 5 kg MT hit my ankle at the recent oz truggy titles, if I had been wearing normal shoes, its a fair chance it would have done serious damage.
