In a commercial for Anheuser-Busch's Bud Light, talk show host Conan O'Brien agrees to shoot a beer commercial only after his agent assures him it will only air in Sweden. "All the Hollywood guys do this," the agent says, shortly before a beer-shilling O'Brien appears on a Jumbotron in New York's Times Square.

Big-time U.S. celebrities rarely appear in commercials in the U.S. But for decades, many Hollywood A-listers, including Madonna and Angelina Jolie, signed lucrative, hush-hush endorsement deals overseas without their U.S. fans knowing. Today, because of the Internet and YouTube, celebs can't keep these deals under wraps. But unlike O'Brien, most don't care.

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Turn on a TV in Tokyo -- or log on to the Internet -- and you can see actor Tommy Lee Jones appear in a Japanese commercial for Suntory Boss Coffee. In another spot that airs in Japan, for Honda Odyssey, a dashing George Clooney steps out of the car to the tune of "Stayin' Alive."

In a commercial directed by Spike Jonze, Brad Pitt acts as a personal assistant for a sumo wrestler. The campaign is for Softbank Mobile, a Japanese conglomerate. These celebrities make as much as seven figures for these kind of deals.

Celebs who were once skittish about having their fans back home find out about their commercial affiliations are signing them even though the spots can travel anywhere by Internet. These stars are, however, choosier about the products they agree to endorse. Sure, agents often negotiate deals so that ads are supposed to only run online in a specific country, but celebs are savvy enough to realize the spots will find their way somewhere else.

"They realize there's a risk, but that's not going to inhibit them from taking these opportunities," says Doug Shabelman, the president of Burns Entertainment, a company that plays matchmaker between companies and celebrities. "They're just being pickier."

Marketers are choosy, too. The Internet, which makes overseas commercials available in the U.S., also makes companies and consumers in other marketers aware of celebrity gaffes and misdeeds.

Last year, French fashion brand Christian Dior dropped Sharon Stone from its advertising in China after she suggested the deadly earthquakes in Sichuan Province were karmic retribution for the Chinese government's treatment of Tibet.