Over the years, more than 400 million people have joined the Skype community, and it continues to grow by leaps and bounds. Josh Silverman, Skype's chief executive officer, is logging on from London and says about 350,000 new users sign up every day.

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Since it's free and easy to operate, Oprah uses this voice communications service to do everything from cook with viewers in their kitchens to tour celebrities' homes. "It's changing the way we do television," Oprah says.

To test the limits of this breakthrough technology, Oprah's embarking on an extreme Skype adventure of her own. "We're going to some places we've never gone before," Oprah says. "We could not have pulled this show off a few months ago. That's just how fast the technology is working."