This 34-year-old semiconductor tester's first stock purchase was supposed to be $3,000 worth of Intel in early 1997. But instead of INTC, Platt typed quickly and invested his money into INTL. "I bought the wrong damn stock," he says about the gaffe.

At the time, however, most stocks were going up. So by the time Platt sold his Inter-Tel stock, its share price had tripled.

Platt doesn't invest in technology stocks anymore. He's a top-down investor, looking for overall market movements, and he says that his electrical-engineering work causes him to "know the trees and not the forest" when it comes to technology.

To find stocks, Platt makes custom screens on Reuters Investor. He screens for expected return by taking the analysts' growth estimates and adding the expected dividends. He then discounts them by 20% to come up with an intrinsic value. If his target is trading below that price, it's a buy. Platt also reads as many SEC documents as he can get his hands on, including the last eight quarterly reports. Platt says that by the time he buys a stock, he'll have put 40 to 50 hours of research into it.

Platt is not a trader. He keeps eight to ten stocks in his portfolio, and his average holding period is four to five months. This strategy has helped him gain an annualized 35% since he started investing regularly in 1999. Right now, Platt is overweighted in cash but recently made two old-line value buys; a transportation and coal play and a purchase in the beer business.

Amateur Guru: James Robert White
2005 return: 36%
Age: 59
Hometown: Islamorada, Fla.
Day Job: retired nuclear engineer
Specialty: technical trading; stocks above their 28-day moving average
Web site: www.ValueForum.com

James Robert "Bob" White spent the last seven years of his career as a nuclear engineer specializing in waste cleanup and safety at Los Alamos National Laboratories. But since 1998, the 59-year-old Floridian has been retired, giving him more time to spend investing. In fact, 12 of his relatives have asked him to manage their money.

White says that "something is always going up somewhere" and that is borne out by his investing record. The last year he lost money was 1986, and even in the dismal 2001 market, he eked out a 1% gain. Over the last three years, he has gained considerably more--adding 47% in 2003, 36% in 2004 and 36% again in 2005.

Though he likes value and income stocks, White trades mainly on technicals. His favorite technical is the 28-day moving average. In order for White to buy or continue to hold a stock, he wants it to be above its 28-day moving average. If all of his stocks are above their 28-day moving averages, then White is happy. But if a stock falls below its 28-day moving average, he says, "You have to have a really good reason to hold onto it. Because usually the market knows better than you do."

With an annual portfolio turnover of 1000% and about 25 stocks in his portfolio at any given time, White is a hyperactive trader.