At TEDIndia, Pranav Mistry demos several tools that help the physical world interact with the world of data -- including a deep look at his SixthSense device and a new, paradigm-shifting paper "laptop." In an onstage Q&A, Mistry says he'll open-source the software behind SixthSense, to open its possibilities to all.

The President of Molecular Frontiers, professor Richard Zare, explains why the sky is blue. This video is from CBS News' Good Questions series, first broadcast in October, 2007.

At TEDxUSC, computer graphics trailblazer Paul Debevec explains the scene-stealing technology behind Digital Emily, a digitally constructed human face so realistic it stands up to multiple takes.

Henry Markram says the mysteries of the mind can be solved -- soon. Mental illness, memory, perception: they're made of neurons and electric signals, and he plans to find them with a supercomputer that models all the brain's 100,000,000,000,000 synapses.

Beau Lotto's color games puzzle your vision, but they also spotlight what you can't normally see: how your brain works. This fun, first-hand look at your own versatile sense of sight reveals how evolution tints your perception of what's really out there.

TED Fellow and journalist Evgeny Morozov punctures what he calls "iPod liberalism" -- the assumption that tech innovation always promotes freedom, democracy -- with chilling examples of ways the Internet helps oppressive regimes stifle dissent.

Journalist Misha Glenny spent several years in a courageous investigation of organized crime networks worldwide, which have grown to an estimated 15% of the global economy. From the Russian mafia, to giant drug cartels, his sources include not just intelligence and law enforcement officials but criminal insiders.

Career analyst Dan Pink examines the puzzle of motivation, starting with a fact that social scientists know but most managers don't: Traditional rewards aren't always as effective as we think. Listen for illuminating stories -- and maybe, a way forward.

Too much of the world lacks access to clean drinking water. Engineer Michael Pritchard did something about it -- inventing the portable Lifesaver filter, which can make the most revolting water drinkable in seconds. An amazing demo from TEDGlobal 2009.

Alain de Botton examines our ideas of success and failure -- and questions the assumptions underlying these two judgments. Is success always earned? Is failure? He makes an eloquent, witty case to move beyond snobbery to find true pleasure in our work.

We're at a unique moment in history, says UK Prime Minister Gordon Brown: we can use today's interconnectedness to develop our shared global ethic -- and work together to confront the challenges of poverty, security, climate change and the economy.

See this Iranian solidarity piece featuring the biggest music and movie stars in the Persian Diaspora--- Shohreh Aghdashloo (nominated for an Oscar for House of Sand and Fog), Sattar and Dariush (both singers with millions of fans around the world) and many others. Organized by Iranian rapper Mams Taylor and actress Shila Vosough, it's a tribute to Neda, the young woman tragically killed on the streets of Tehran --- a 'We Are The World' meets 'Yes We Can'.