The stock of a steel company rises 700% in just over a year. The currency of an emerging country plunges 50% in a week and wipes out billions of dollars from the accounts of North American investors. The margin deposit on a futures contract increases ten-fold in less than three months. These are just a few examples of some opportunities for gains and losses that financial markets can generate. Some investors have turned the gyrations of financial markets into fortunes -- a couple of high-profile names being Warren Buffett and John Maynard Keynes. Many other.