Back in September, Wynn Resorts CEO Steve Wynn was spending two hours each day on Chinese lessons. At age 65, Wynn is worth $3.4 billion -- yet he's still learning new tricks.

Why? Because the Wynn Macau -- Mr. Wynn's latest megacasino -- was getting set to open just off the coast of China. That's right on the doorstep of some 3 billion potential customers.

Big bets for big paydays
How has the Wynn Macau fared? Analysts see it tracking above previous estimates, and contributing some $300 million in EBITDA in 2007.

But Steve Wynn isn't the only billionaire going gaga over foreign markets. Wynn rival and Las Vegas Sands CEO Sheldon Adelson, himself worth $26.5 billion, is making a similar investment in Macau's potential. Then there's Diageo (NYSE:DEO), which recently acquired a more than 40% share of China's Sichuan Chengdu Quanxing Group in order to build out a domestic liquor brand in that country. Just a few days ago, Intel (NASDAQ:INTC) announced plans to build a $2.5 billion manufacturing plant in China as CEO Paul Otellini called the country Intel's "fastest growing market."

Entrepreneurs and investors alike
Meanwhile, there are the master investors who have been buying up Chinese stocks at a rapid clip. Chris Davis and Mark Hillman have $31 million and $4.5 million stakes, respectively, in China Life Insurance (NYSE:LFC); Charles de Vaulx recently purchased 20,000 shares of Suntech Power (NYSE:STP); and New York's Horizon Asset Management seems to be increasing its stake in China Southern Airlines (NYSE:ZNH) even as the stock has more than doubled in less than a year.

Even Warren Buffett stoked the international frenzy earlier in '06, with purchases of PetroChina and Israel's Iscar Metalworking.

The question we have to ask
So -- and you had to know I was coming around to this -- what have you been adding to your portfolio lately?

Me? I know I'm underexposed to international stocks, and I've resolved to make 2007 the year I do something about that. One place I'm set to start is at our new Global Gains international investing service. You can join me free for 30 days by clicking right here.

This article was originally published on Jan. 19, 2007. It has been updated.

Tim Hanson owns shares of Wynn Resorts. Diageo is a Motley Fool Income Investor recommendation. Intel is an Inside Value choice. No Fool is too cool for disclosure.