According to serious environmentalists, one of the worst ideas of 2008: Carbon Offsets
The wanna-be environmentalist's "Get out of Jail Free" card, carbon offsets enable companies or individuals to invest in tree farms or wind power as a way to compensate for their carbon footprints. Problem is, offsets don't change behavior. They're just the green equivalent of confession, making people feel better about their eco-sins but not stopping them from committing them.