I was reading this question which seemed a totally weird thing to worry about and sparked my question.
I've always disregarded stop signs, lights, crossings and waving policemen as basically irrelevant since I'm on a bike and don't have a number plate or a licence that could be suspended.
So far I've only been hassled once by a cop telling me I have to ride on the sidewalk after I went through a couple of red lights next to his vehicle, and had a few yell at me about wearing a helmet which I just ignored.
Are there any realistic consequences apart from the obvious safety concerns (which I'm not asking about) to doing whatever you want on the road?