In our article on transportation innovations, we told you all about London's congestion pricing . But apparently, the congestion pricing is causing a bit of a stir in London, because diplomats refuse to pay (they say its a tax, and diplomats are tax free). The U.S. is the worst offender. We owe 1.5 million pounds. The mayor of London has called our representative to the Court of St. James's "a venal little crook." Ouch.