Deck the Halls with Greenhouse Gases

According to some in my social circle, holiday cards may warm the heart but they also contribute to global warming. Therefore there has been an influx in holiday emails. I say bah-humbug. Mother Earth and her side kick Al Gore may turn me into compost for saying this but...I'm sending out cards anyway. No guilty conscience here. The United States Postal Service thanks me. I'm not ashamed to say that I love being on the receiving end as well. How often do I get to open an envelope with no "amount due" listed?