Operationally, the transactions were fairly trivial.

Think about spam filters; if email didn't come from someone that someone you know knows, that's an important signal, and one we could embed in the environment; we just don't. I just want the world to be filtered through my social graph.

The tools that a society uses to create and maintain itself are as central to human life as a hive is to bee life. Though the hive is not part of any individual bee, it is part of the colony, both shaped by and shaping the lives of its inhabitants.

Anybody who predicts the death of cities has already met his spouse.

Carpooling is important for urban density, air pollution and other reasons, but carpooling is not the kind of thing that actually changes the energy equation.

You used to have to own a radio tower or television tower or printing press. Now all you have to have is access to an Internet cafe or a public library, and you can put your thoughts out in public.