Gordon Gekko: "Greed is good"

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"Buy low, sell high" was the guiding mantra of the 1980s - the decade of boom and eventually bust. As cliched as this principle of making money sounds, the basic idea that to make a stash of cash you have to move up with the financial markets is a safe one. And it also ushers in that second commandment of investors: that you have to speculate (when the market is low) to accumulate (when the markets rise).

Take your average house in Britain. Over the past 10 years, starting from a time when the property market had fallen dramatically, your typical dwelling has risen from £68,085 to a whopping £196,745 - bagging you nearly £130,000. And there we have the two principles: buying low, selling high, and speculating in a market that had bottomed out.

OK, so perhaps Gordon Gekko (the character Michael Douglas played in the film Wall Street) may have frowned upon a measley £130,000 over a decade and plumped for something more lucrative, like this little lot in our world's most profitable investments picture gallery. Whether it's entrepreneurs making money, or city traders pouncing on the stock exchange, money makes the globe gyrate.

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