If you're trying to impress people with your carbon footprint, you may not want to flaunt your phone unless it's made by Sony or Sony Ericsson. Those are the only electronics makers that scored above 5/10 in the latest edition of Greenpeace's Guide to Greener Electronics.
The organization tried to explain why the 18 companies that were assessed seemed to rank so low on its scale (PDF). "Electronics giants pay attention to environmental performance on certain issues, while ignoring others that are just as important. Philips, for example, scores well on chemicals and energy criteria, but scores a zero on e-waste since it has no global take-back polices," said Iza Kruszewska, Greenpeace International's toxics campaigner.
Sony Ericsson got high marks in the chemicals category, attributable in no small part to its ban on PVC beginning with this year's products, according to Slashphone. If you do carry a different brand, you might at least be able to disguise it with a case made from recycled tires.