Edward Tenner, historian of technology and culture, shares the intrigue of unintended consequences: “I didn’t always love unintended consequences, but I have learned to appreciate them.”

Eythor Bender brings out Amanda Boxtel, a wheelchair user wearing an astonishing new exoskeleton. She is walking.

Eli Pariser reveals some frightening data about our online identities: “I call it the “filter bubble.” Personalized data that is all you see. You don’t even know what you don’t see.”

Chinese artist Ai Weiwei says: “I’m living in a society where freedom of speech is not allowed … I’m trying to involve my art with society, to build possibility.”

Ralph Langner is a security consultant with a big job: “The idea behind the Stuxnet worm is quite simple: We don’t want Iran to get the bomb.”

Googler Sebastian Thrun talks about the new Google car. “Our work has focused on building cars that can drive themselves. Anywhere, on any street.”

How can you build a car for the blind? Roboticist Dennis Hong shows us how: laser range finders and scanners, GPS, cameras feeding into a driving computer.

Philip Zimbardo presents a problem: “The Demise of Guys.” Girls now outperform guys at all levels of school from elementary to grad school. Why? He leaves the solution up to us.