William Kamkwamba: How I harnessed the wind

Basic English Grammar: Have, Has, Had

The puzzle of motivation | Dan Pink | TED

Arthur Benjamin: Teach statistics before calculus!

Richard St. John: "Success is a continuous journey"

Kevin Surace invents eco-friendly drywall

Yves Behar's supercharged motorcycle design

Hans Rosling on HIV: New facts and stunning data visuals

Al Gore: Alarming new slides of the worsening climate crisis

Alex Tabarrok on how ideas trump crises

Unveiling game-changing wearable tech | Pattie Maes

Mosquitos, malaria and education | Bill Gates

Andy Hobsbawm: Do the green thing

Helping humans and animals live together | Jane Goodall

Marisa Fick-Jordan: The wonders of Zulu wire art

Adam Grosser: A mobile fridge for vaccines

Murray Gell-Mann: Do all languages have a common ancestor?

Ngozi Okonjo-Iweala: How to help Africa? Do business there

New thinking on the climate crisis | Al Gore

Alan Kay: A powerful idea about teaching ideas

Isabel Allende: Tales of passion | TED

Blaise Aguera y Arcas: Jaw-dropping Photosynth demo

What separates us from chimpanzees? | Jane Goodall

Bill Clinton: TED Prize wish: Let's build a health care system in Rwanda

Hans Rosling: Debunking third-world myths with the best stats you've ever seen

Wade Davis: Cultures at the far edge of the world

Majora Carter: Greening the ghetto | TED

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