The idea: Offset less-than-green actions by supporting groups that invest in the environment.
The hitch: Offsetters are largely unregulated and prices vary wildly - from $5 to $60 a metric ton of carbon dioxide.
Bill Burtis of Clean Air-Cool Planet, which evaluates offsetters, prefers ones that fund new projects rather than direct money to existing groups.
A solid pick: British-based Climate Care, which among other things pays for wind turbines in India.
