Clear Thinkers favorite — USC Urban Economics Professor Peter Gordon — is one of the participants in this Wall Street Journal Econoblog from earlier this year, in which the subject is one near and dear to most Houstonians — that is, the cost of traffic congestion, the problems that such congestion poses for urban areas and the policy options that are effective in dealing with the problems. The discussion is a very good overview of the policies and the problems involved in implementing them.