I've just realised that this has been in the drafts folder for a while (dunno why). I'm posting it now as it's a subject that I've raised in the previous post on libertarianism.
A good couple of posts from Kevin Harris here and here. Watch the Channel Four news piece that he links too if you’re in a hurry.
A while ago, I suggested that car-size should determine part of the rate of Road Tax because of the ‘eye-contact’ factor. I still think that it is the one obvious weakness in the ‘shared space’ idea, but it's not enough of a weakness to put anyone off it.