But I really like San Francisco in the fall

"Ian Roberts and Fiona Godlee published an editorial in the British Medical Journal on the "carbon footprint of medical conferences." They determined that flights destined for the annual conferences of the European Respiratory Society and the American Thoracic Society put more carbon dioxide into the atmosphere than do 110,000 Chadians or 11,000 Indians in an entire year. The problem does not end with medical researchers. Scholars of all stripes travel to meet, greet, and, in one of our more ironic roles, preach the gospel of sustainability." (Thanks D.)