"Don't be evil. We believe strongly that in the long term, we will be better served — as shareholders and in all other ways — by a company that does good things for the world even if we forgo some short term gains" -- Google's 2004 IPO Prospectus (http://people.ischool.berkeley.edu/~hal/Courses/StratTech09/...).

Binding or not, it's a social contract, and it could mean the world if Google stands by it.