How do you do it when you are wronged by a motorist e.g. close pass, left hook, general crappy driving?
I used to gesticulate a lot but you only end up winding yourself up even more and can put yourself in more danger drifting over the road while waving your arms about.
Not to mention you get the odd nutter who will stop; fighting in lycra with cleats and a ton of miles in the legs isn't a good idea.
I tend to mumble or if it's really dangerous shout knowing full well no one can hear. I think the more it happens the less it bothers you which isn't a great way of viewing bad driving.