Robert Neuwirth: The "shadow cities" of the future

Peter Gabriel: Fighting injustice with a videocamera

Phil Borges: Documenting our endangered cultures

Bjorn Lomborg: Global priorities bigger than climate change

Wade Davis: Cultures at the far edge of the world

Richard Baraniuk on open-source learning

Do schools kill creativity? | Sir Ken Robinson | TED

Majora Carter: Greening the ghetto | TED

Dean Ornish: The world's killer diet

Secrets of success in 8 words, 3 minutes | Richard St. John

If I controlled the Internet | Rives