Susan notes: Thanks to TED for making TED Talks downloadable and embeddable, and for providing the biographical information that goes along with them.

Athlete, actor and activist Aimee Mullins talks about her prosthetic legs -- she's got a dozen amazing pairs -- and the superpowers they grant her: speed, beauty, an extra 6 inches of height ... Quite simply, she redefines what the body can be.

Aimee Mullins was born without fibular bones, and had both of her legs amputated below the knee when she was an infant.

She learned to walk on prosthetics, then to run -- competing at the national and international level as a champion sprinter, and setting world records at the 1996 Paralympics in Atlanta.

Susan notes: Thanks to TED for making TED Talks downloadable and embeddable, and for providing the biographical information that goes along with them.

Jane Poynter tells her story of living two years and 20 minutes in Biosphere 2 -- an experience that provoked her to explore how we might sustain life in the harshest of environments.

This is the first TED talk drawn from an independently organized TEDx event, held at the University of Southern California.

Poynter is one of only eight people to live in Biosphere 2 for two years. In 1991, she and seven others were locked in a three-acre, hermetically-sealed environment in the Arizona desert. Nothing was allowed in or out, and everything had to be recycled. Poynter, and the rest of the team, endured dangerously low oxygen levels and constant hunger, but they survived -- something many scientists said was impossible. 

Susan notes: Thanks to TED for making TED Talks downloadable and embeddable, and for providing the biographical information that goes along with them.

A happy song about global warming, from Jill Sobule.

Jill Sobule first found her place in music history with the controversial 1995 hit "I Kissed a Girl." The song's silly sweetness masked its significance: It broke new ground as the first Top 40 hit to deal with overtly gay themes.

This approach -- packaging hard-hitting social commentary in a wrapper of whimsy -- has defined Sobule's career. Her endearing story-songs veer from fanciful storytelling to forceful satire and back again, covering a wide range of political and social issues from climate change to prostitution; anorexia to anti-semitism.

Susan notes: Thanks to TED for making TED Talks downloadable and embeddable, and for providing the biographical information that goes along with them.

We know the negative images of Africa -- famine and disease, conflict and corruption. But, says Ngozi Okonjo-Iweala, there's another, less-told story happening in many African nations: one of reform, economic growth and business opportunity.

Ngozi Okonjo-Iweala, a director of the World Bank, was Nigeria's Finance Minister and then briefly Foreign Affairs Minister from 2003 to 2006, the first woman to hold either position.

During her tenure as Finance Minister, she worked to combat corruption, make Nigeria's finances more transparent, and institute reforms to make the nation's economy more hospitable to foreign investment. The government unlinked its budget from the price of oil, its main export, to lessen perennial cashflow crises, and got oil companies to publish how much they pay the government.

Susan notes: Thanks to TED for making TED Talks downloadable and embeddable, and for providing the biographical information that goes along with them.

In this hopeful talk, Jehane Noujaim unveils her 2006 TED Prize wish: to bring the world together for one day a year through the power of film.

Two weeks before the US invaded Iraq in 2003, Jehane Noujaim gained access to both Al Jazeera and the US military's Central Command offices in Qatar. By being in the right place at that very wrong time, she caught the onset and outbreak of the Iraq war on film. The resulting documentary, Control Room, exposed the very divergent ways the Arabs and the West covered the war.

Being raised between Egypt and the US, the exploration of culture is one of Jehane's driving forces. Her reason for making the film: "It's important for everyone, simply as individuals, to try to understand different people and different cultures, but it's especially important for people in the United States because we affect so much of the world beyond our borders."