One of the most despised investments on the planet, Greece’s top bank has lots of upside, writes Nicholas Vardy in Global Bull Market Alert.

I recently laid out my "Are You Crazy?" investing strategy, which requires that when you describe an investment to your friends, the reaction should be: "Are you crazy?"

I am issuing this special alert to highlight an “Are you Crazy?” pick that I believe could double—or even triple—before the end of 2011.

And it is ... (drum roll, please) ... the National Bank of Greece SA (NYSE: NBG).

I hear the cries of “are you crazy” here in London.

After all, ratings agency Fitch just recently cut the long-term ratings of the National Bank of Greece to BB+ from BBB- while it maintained a “negative outlook” for its prospects.

Here's why I think Fitch and the other naysayers are wrong, and why National Bank of Greece will be a big winner for patient investors...

First, downgrades or not, the European Union cannot afford to let major European banks go under. The National Bank of Greece's position is much like that of Citigroup (NYSE: C) in the United States at the height of the financial crisis. And savvy investors like hedge fund manager David Tepper now have made close to five times their money in Citi over the past two years by having the foresight to buy it near the bottom.

Smart Money Sniffs Opportunity
Second, negative headlines notwithstanding, we already may have seen the bottom in the share price of the National Bank of Greece. The European banking sub-index has regained the ground it lost during the Irish bailout at the end of last year. Bank stocks now are trading at their early November levels in spite of the concerns about the debt of countries such as Portugal and Belgium. National Bank of Greece stock has just traded over its 50-day moving average for only the second time since its collapse at the end of 2009. [The ADRs traded up 7% in New York Tuesday to top $2 for the first time since early November. They’ve rallied 37 off the bottom on Jan. 10—Editor.]

Third, Greek banks are slowly, but surely, being upgraded by investment banks. Last week, Greece’s third-largest lender, Alpha Bank, was raised to “neutral” from “underperform” by investment bank Credit Suisse. In another positive sign, option call volume on National Bank of Greece—bets that NBG's share price will increase in the near future—was running at close to three times the daily average last week. Speculators are piling in.

As with the Bank of Ireland (NYSE: IRE), I want you to think about this pick like an option. As with an option, the stock will bounce around like crazy. But unlike an option, it will not expire or lose its value over time.

Because of the unusual nature of this pick, I am not placing a stop on it. Nor am I recommending options. Holding the stock itself will give you a wild enough ride.

(Full disclosure: I hold the National Bank of Greece stock both in my personal accounts and for my clients at my investment firm, Global Guru Capital.)

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