Four years ago, my wife went to visit her sister in New York. She came back toting bags of clothes for our 1-year old daughter from "this amazing new store called 'H&M.'" Well, I may not be the sharpest knife in the drawer, but I have missed enough investing opportunities by failing to heed my wife's enthusiasms that I made a note and did a search for H&M. Sure enough, there it was, Hennes& Mauritz(Pink Sheets: HMRZF). It's a Swedish company -- one of the world's largest clothing retailers. And it's publicly traded.

Had my wife not mentioned this company to me, I would have remained ignorant to its existence, let alone its popularity, and I definitely wouldn't have seen its potential as an investment. I listened to my wife, found out what she liked about H&M and its products, and I checked the company's financial statements. I discovered that many, many people apparently felt the same way, since stores were (and are) spreading like wildfire. This has been a great investment for us.

The moral of this story is: If you want to have an instant edge in investing, think like a woman.

I can hear the hackles being raised among people who have no trouble thinking like women because they are, in fact, women. Am I trying to be insulting? No, absolutely not. I'm counseling the investing version of what old-time baseball great "Wee Willie" Keeler called his batting secret: "I hit 'em where they ain't." This is a math problem. And it's also, truth be told, a story of using men's man-ness against them.

In the majority of American families, one person tends to be the primary investor. This person also tends, more often than not, to be the husband. This is changing, but it still holds that the vast majority of folks managing their family investment accounts are the good old alpha males. Lest I fail to put too fine a point on this, I do not necessarily think this is a good thing, for reasons that I'll get to in a moment. But it is what it is.

The guys who handle the investments are the very same ones you can find in any mall in America, sitting miserably in a corner while their wives/girlfriends/daughters are shopping in shoe and clothing stores. Every inch of these guys' beings screams out "lack of interest."

Is it any surprise that when these same fellows scour for investment ideas, one of the last places they look is at the makers and sellers of products their wives consume every day? No, we guys shop for stocks the same way we do anything else -- we want the newest, the coolest, the most high-tech. We're gearheads. Our investments must involve lasers, cutting-edge trends, and horsepower measured in the hundreds. Space launches? Righteous. Ann Taylor (NYSE:ANN)? Please, my buddies might laugh at me. Playtex (NYSE:PYX)? You have got to be kidding.

Avoiding girl stuff
Do you hear that, ladies? We men not only undervalue the experience of going shopping with you, but we also forgo a huge amount of knowledge about what stores -- and what companies -- are doing well. If you pay attention to where you buy clothing, what stores your friends favor, and what stores you notice are extremely busy, you have a huge investing advantage over men. We're too busy being miserable, or thinking about whether nanotech or fiber optics will be the bigger long-term winner.

Think about it. In the late 1990s, some of the stocks with the highest, most insane valuations -- Avanex (NASDAQ:AVNX), Global Crossing (NASDAQ:GLBC), and the like -- also happened to have the most audacious business plans or bleeding-edge technology. You can nearly hear the all-male chorus: "Profits? Who cares! Look how FAST this thing goes!" Meanwhile, Chico's (NYSE:CHS) kept opening stores, one after another after another.

Invest where you spend
Your wallet may be the first thing attracted to a company that actually deserves your investing dollars as well. My family hews to the stereotypical split of duties: I manage the investments; my bride manages the shopping. My investing performance has improved substantially just by paying attention to where she likes to shop, for the very reason that she helped me realize that success in investing doesn't necessarily mean going for the complex or the difficult-to-understand. Rather, you can make a bunch of money by seeking out the ignored and misunderstood.

I'm not that huge of a gearhead, and I pretty much got that I didn't "get" technology. That didn't stop me from losing a shekel or two on Openwave (NASDAQ:OPWV) back in the day. What I loved, and still love, is the exotic, be it an exotic security, an exotic company, or an exotic location. That's my jones.

A Brazilian story that doesn't involve caipirinha
So in the mid-1990s, I focused on what is going to happen when Telecomunicacoes Brasileiras (NYSE:TBH) got privatized and broken up into 12 smaller companies. It was grueling work figuring out all of the moving parts, deciding whether the umbrella holding or one of the new subsidiaries would be a better bet, working my way through the lawsuits, and so on. Meanwhile, my wife is raving about the deals she's gotten at Target (NYSE:TGT), which at the time still traded as Dayton Hudson.

My slogging continues. I start working on teledensity and growth statistics for each Brazilian region and trying to understand Brazilian accounting and corporate governance. My bride and her friends agree to meet at Target and go afterwards for lunch. She's furnished an entire room in our house just from Target.

Finally, I decide that TeleBras is just too complicated and that I can't get a handle on what's happening. It's only then that I turn my eyes to look for something simpler. Well, how about Target? Huh. It's doubled and looks expensive. That's no good.

But as you can see, I would have been much better off had I simply took note of what was going on around our house. Had I thought about where our money was going, I'd have saved myself countless hours of research that, while interesting, came to naught. Had I paid attention to what she was passionate about, I may have been able to draw an easy parallel between where our money was going and fertile grounds for investment.

That's when the switch flipped. The next time around, I didn't make the same mistake. When my bride said she'd found a great online service called (NASDAQ:OSTK) two years ago, I was ready. Ditto H&M.

It's a simple story, one that is at the core of Foolish investing: If you want to find great investments, one really easy way is to watch where your money is going. And if you're not the chief spender in the family, you need to get in tune with the person who is. And for many of us guys, that means we need to start looking around when we're stuck outside some changing room in a mall. It's not torture. It's opportunity.

Bill Mann owns shares of Hennes & Mauritz (thanks, honey!). Since Bill's recommendation of Overstock in the inaugural issue of the Motley Fool Hidden Gems newsletter, it has increased 225%. It was his second-best pick in that issue.

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