"I love cities, and I love city governments in particular. But in politics it would have taken me 8 years from implementing a policy before I would get to see the feedback. With programming I could model the same policies and see the impact immediately. Technology is a far more efficient way to test."

"I loved couriers. You had this transfer of physical information happening throughout the city and the world. Someone picking up the package, putting it in a bag, going somewhere, taking it out of the bag, giving it to someone else. I thought that was so cool. I wanted to map it, to see that flow on a big screen."

"It's a matter of invitations versus context. Twitter is really good at providing context, like, I''m having coffee at Third Rail Coffee.' Foursquare is about invitations to places. In this respect Foursquare has started to replace Yelp for me."

"Those words are from Lynda Barry's novel 'Cruddy.' I've carried them with me for some time. There's a lot in my life I wasn't expecting. One is the realization that I stood at this pulpit and delivered a reading for my own graduation...15 years ago. Unexpectedly, I'm old."

"I think that great programming is not all that dissimilar to great art. Once you start thinking in concepts of programming it makes you a better person...as does learning a foreign language, as does learning math, as does learning how to read."

"What's interesting about Twitter and the influencers that someone follows - like, say, Shaquille O'Neal - is that they see someone who is using the exact same tools that they have access to, and I think that inspires this hope to be able to really engage with someone like him."

"A number of people in the United States, almost everyone, is using plastic cards to pay for things, but it's extremely difficult to accept these cards. So let's make it's easy and take more and more of the friction out as we can."