It's actually more than just going carbon neutral across the company; Microsoft is making each of its individual divisions responsible for offsetting its own emissions. That's kind of a big deal, especially because a division that uses enormous server farms -- cloud computing, anyone? -- uses tremendous amounts of energy. Critics like Greenpeace aren't crazy about the method, which allows divisions to purchase carbon offsets -- they'd prefer the company turn to renewable energy sources. Can't win 'em all.