It's hard not to think of Matt Damon without a song by the American comedian Sarah Silverman coming to mind (the lyrics are too racy to reprint). Such is the actor's good grace and humour, he agreed to appear in the video. Damon (above) is established in Hollywood - a fixture of the Jason Bourne films, among others. But his interests spread wider than action movies. In the past few years, he has produced The People Speak, a documentary about social change in the US, and narrated Inside Job, which documented the 2008 financial crisis. He has also become an energetic campaigner, as a co-founder (with George Clooney and others) of both Not On Our Watch, which aims to stop global atrocities such as that in Darfur, and the H2O Africa Foundation (now part of water.org), working to provide clean water in poor countries. He campaigns on home soil, too - last month, he wowed thousands of teachers when he addressed their Washington march against standardised testing. Many later called for him to run for president. After all, he wouldn't be the first thesp in the White House.
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