Carbon offsets

Back to feet of carbon for a moment. Last night I reread an article about Al Gore in Wired magazine (May '06) that mentioned his use of carbon offsets. He and Tipper regularly calculate their home and business energy use, including their frequent international travel, then they purchase offsets. Last year (2005), they redeemed their million miles of air travel by giving money to an Indian solar electric company and a Bulgarian hydroelectric project.