Got to get some karma points just for not creating all that carbon footprint? (Of course, as my virulently non-tech wife points out, the data centers that run these things make their own carbon footprint-- no way to quantitate that

.)
Actually, some of the data-centers have taken green initiatives, and I know of at least one that is 'green' powered. It is in the Northern great plains, and near large wind-farms. It buys the balance from other 'green' sources.
Wasn't a fit for us, but it is out there (and growing).
Google has been experimenting with at-sea data-centers arguing 'green' reasons. Don't know if anyone else has read Neal Stephenson's
Cryptonomicon or
Snow Crash , but floating Cyber-Nations would be a valid alternative explanation.