There's a new article from a few days ago on CNET that describes exactly what we're doing here at Rally, trying to become more efficient to become greener and more profitable.  The author makes the excellent point that the goal needs to be "sustainability" a key difference from mere "greening".  No company can afford to implement every idea for a "greener" company, but if they can become more efficient, they can be more environmentally friendly while raising margins.