3. Caterpillar ( CAT) Company profile: Caterpillar is the world's largest maker of heavy construction equipment, including bulldozers, excavators, and loaders. It also produces engines for its own off-highway vehicles and others' machines. Investor takeaway: Its shares are up 24% this year and have a three-year annualized return of 56%. Its top markets, especially mining, are booming internationally, particularly in Asia, and its strong brand name usually makes it a top choice. When construction picks up domestically, it will do even better. Analysts give its shares one "buy" rating and four "holds." 2. AllianceBernstein ( AB) Company profile: AllianceBernstein, with $406 billion in assets under management, offers investment management services to institutional, retail, and private clients. Its products include mutual funds, hedge funds, and separately managed accounts. Morningstar said its wide moat characteristics include "a meaningful amount of assets under management, a diverse mix of assets, and broad distribution by channel and geography." Investor takeaway: AllianceBernstein's shares are up 10% this year, even after losing 13% last Friday alone, after the company reported a nearly $200 million fourth-quarter loss and a steep drop in revenue. That's because its clients continued to withdraw money from stocks as they turned risk-averse because of the market volatility throughout 2011, the company said. Its shares have a three-year annualized return of 5.5%. They get two "hold" ratings from analysts. 1. Weight Watchers ( WTW ) Company profile: Weight Watchers is a weight-management company with operations in more than 25 countries. Consumers buy more than $4 billion of Weight Watchers-branded products each year, and every week approximately 1.8 million people attend Weight Watchers meetings worldwide. The company encourages healthy weight loss through exercise, nutrition, and portion control. Investor takeaway: Its shares are up 36% this year and have a three-year annualized return of 55%. Morningstar says "the company benefits from a wide economic moat because it would be extremely difficult for a competitor to replicate the company's brand recognition and meeting infrastructure to compete against Weight Watchers in a significant way." Weight Watchers gets three "buy" ratings and two "holds" from analysts. S&P lowered its rating on Weight Watchers to "sell," from "buy," on Feb. 9, due to its valuation. The company's share price of $77.37 exceeds S&P's price target of $67, although S&P said that "long term, WTW should benefit from the rise in obesity in the U.S. and abroad, as well as on-line subscriber growth and an increase in male subscribers." >>To see these stocks in action, visit the 7 Stocks With Double-Digit Retruns This Year portfolio on Stockpickr.