When it comes to world changing projects, it's hard to get any better than TED. With a mission to share "Ideas worth spreading" the talks have become a household name and a go-to for inspiration, peaks at cutting edge innovation and thinking... all explained in a maximum of 18 minutes per talk. Notable speakers have included Bill Clinton, Bill Gates, Jane Goodall, Richard Dawkins, Malcolm Gladwell, Al Gore, Gordon Brown, Google founders Larry Page and Sergey Brin, and many Nobel Prize winners.
TED (Technology, Entertainment, Design) was actually founded as a one-off event in 1984. That initial conference lost money, and annual conferences weren't scheduled until 6 years later in 1990. Since June 2006, TED talks have been available for free viewing online, leading to their massive popularity with the general public. It's a good thing too, because the current price for main conference tickets is $7,500!