BOSTON ( TheStreet) -- U.S. stocks with market values of $500 million to $2 billion, so-called small-caps, have delivered an average gain of 25% so far in 2010, placing second after mid-caps, which rose 26%. Still, the top-performing small-caps led the market, with many doubling and some even tripling or quadrupling. Here are 10 of the best small-caps of 2010.

10. Glimcher Realty Trust ( GRT) more than tripled in 2010. Glimcher, based in Columbus, Ohio, owns and develops shopping malls. It is structured as a real estate investment trust, or REIT, so it is required to pay out the majority of its income to shareholders.

12-Month Sales Growth: -8.4%
12-Month Net Income Growth: -102%
Cash Flow Multiple: 9 (52% peer discount)
Quarterly Operating Profit Margin: 28%

Analyst Opinions: Of analysts covering Glimcher, two, or 29%, advise purchasing its shares, three recommend holding and two suggest selling. With mall occupancy of 93% and store sales up 4% in the third quarter, business seems more stable for Glimcher. But, it is running net losses and has a debt-to-equity ratio of 4.1. Citigroup expects its stock to rise 8% to $9. RBC foresees a 16% drop to $7.

9. Questcor Pharmaceuticals ( QCOR) has surged 220% in 2010. The Union City, Calif.-based company has grown 12-month sales 25%. Its drug Acthar, used to treat multiple sclerosis, saw a 129% jump in quarterly paid prescriptions.

12-Month Sales Growth: 25%
12-Month Net Income Growth: 7.6%
Cash Flow Multiple: 19 (68% peer premium)
Quarterly Operating Profit Margin: 54%

Analyst Opinions: Just three researchers follow Questcor, with two rating its stock "buy" and one ranking it "hold." Oppenheimer forecasts that the stock will advance 24% to $19. The shares certainly have technical momentum. They've appreciated 44% in the past three months. Acthar was recently approved by the FDA as a safe treatment for infantile spasms, expanding the drug's revenue potential. It is now approved to treat more than 29 disorders.

8. Trimas ( TRS) shares have advanced 230% in 2010. Trimas makes sealants, screws and engine parts with packaging, industrial and aerospace applications. Its 12-month profit has doubled.

12-Month Sales Growth: 10%
12-Month Net Income Growth: 119%
Cash Flow Multiple: 10 (31% peer discount)
Quarterly Operating Profit Margin: 13%

Analyst Opinions: Of analysts covering Trimas, four, or 57%, advise purchasing its shares and three recommend holding them. A median target of $22 suggests the stock has run past fair value. Jefferies and KeyBank value the stock at $20, implying that it is 13% overvalued. However, its forward earnings multiple of 16 and cash flow multiple of 10 reflect machinery industry discounts of 26% and 31%.

7. Travelzoo ( TZOO) is an Internet media company that publishes travel and entertainment offers, with 20 million subscribers worldwide and countless Web site users. It has North America and Europe units.

12-Month Sales Growth: 20%
12-Month Net Income Growth: 5,427%
Cash Flow Multiple: 40 (105% peer premium)
Quarterly Operating Profit Margin: 21%

Analyst Opinions: Just two researchers follow Travelzoo, which has a market value of $707 million. One ranks its stock "buy" and one rates it "hold." Wedbush, the more reputable of the two, values the stock at $50, suggesting 26% of potential upside. At a forward earnings multiple of 48 and a book value multiple of 17, Travelzoo appears expensive. But its PEG ratio, a measure of value relative to growth, of 0.7 reflects a 30% discount to fair value.

6. MIPS Technologies ( MIPS) develops embedded processor intellectual property for digital entertainment and wired and wireless communication products. It licenses the property to other companies. Its stock has more than tripled in 2010.

12-Month Sales Growth: 20%
12-Month Net Income Growth: 1,159%
Cash Flow Multiple: 32 (119% peer premium)
Quarterly Operating Profit Margin: 40%

Analyst Opinions: Three researchers rate MIPS' shares "buy," two rate them "hold" and one ranks them "sell." But, the stock has passed the median target of $13, implying that it is 14% overvalued. The stock is just beneath the highest individual price target, at $15, suggesting a cap on upside. But, business fundamentals remain strong. Quarterly revenue gained 40%. At 29-times forward earnings, the stock costs twice the industry average.

5. Polypore International ( PPO) sells microporous membranes, used in separation and filtration processes, to energy and technology companies. They are utilized in lithium and lead-acid batteries.

12-Month Sales Growth: 17%
12-Month Net Income Growth: -177%
Cash Flow Multiple: 16 (4% peer premium)
Quarterly Operating Profit Margin: 19%

Analyst Opinions: Of analysts evaluating Polypore, six, or 60%, advocate purchasing its shares and four suggest holding them. None are advising clients to sell. Wedbush offers the highest price target, expecting the stock to rise another 19% to $49. JPMorgan rates Polypore "neutral" with a $27 target, suggesting 35% downside. Polypore's forward earnings multiple of 27, book value multiple of 5.4 and sales multiple of 3.1 represent industry premiums.

4. Mesabi Trust ( MSB) is a grantor trust with iron ore properties in Minnesota. It derives income from the properties and distributes it to holders. It yields 4.2% with a three-year distribution growth rate of 18%.

12-Month Sales Growth: 263%
12-Month Net Income Growth: 286%
Cash Flow Multiple: 25 (at peer parity)
Quarterly Operating Profit Margin: 98%

Analyst Opinions: Mesabi is an unusual investment product with seemingly outdated rules. It will continue to pay distributions until the resources at its properties are exhausted. Estimating when that will be is a daunting task. Lured by yield, investors poured into the trust in 2010. Its forward earnings multiple of 19 is on par with the metals and mining industry average. This is a unique investment and its yield is no longer high enough to justify the idiosyncratic risk.

3. Entropic Communications ( ENTR) is a semiconductor company, specializing in building chips and integrated circuits that enable connected home entertainment. It has surged 269% in 2010.

12-Month Sales Growth: 58%
12-Month Net Income Growth: 113%
Cash Flow Multiple: 43 (192% peer premium)
Quarterly Operating Profit Margin: 18%

Analyst Opinions: Of researchers covering Entropic, 15, or 88%, still rate it "buy." One rates it "hold" and one ranks it "sell." A median target of $12.33 suggests a gain of 10%. Barclays predicts the stock will rise 24% to $14. JPMorgan, on the other hand, sees a marginal advance to $12. A forward earnings multiple of 15 is on par with the peer average. Entropic's book value multiple of 8 signifies a sizable premium.

2. IDT Corp. ( IDT) is a telecom and energy company, based in Newark, N.J. Its telecom platform company sells pre-paid and rechargeable calling cards. Its Genie Energy subsidiary resells natural gas and electricity throughout New York state.

12-Month Sales Growth: 0.1%
12-Month Net Income Growth: 133%
Cash Flow Multiple: 11 (164% premium)
Quarterly Operating Profit Margin: 2.4%

Analyst Opinions: There are no sell-side analysts covering IDT, which has a market value of just $546 million. Still, its fundamental improvement is apparent. IDT swung to a fiscal first-quarter profit of $16 million, or 70 cents a share, from a year-earlier loss of $3.5 million, or 17 cents. Revenue grew 9.2% to $357 million. Management is considering spinning off its Genie Energy subsidiary and is exploring options to license or sell its VoIP intellectual property.

1. Wabash National ( WNC) makes and markets customized truck trailers and related transportation equipment. It also makes steel flatbed and dropdeck trailers. It has posted net losses for three quarters.

12-Month Sales Growth: 0.2%
12-Month Net Income Growth: 40%
Forward Earnings Multiple: 29 (33% peer premium)
Quarterly Operating Profit Margin: -2.5%

Analyst Opinions: Of analysts evaluating Wabash, five, or 83%, rate its stock "buy." None rank it "hold." One rates it "sell." A median target of $13.80 suggests an impending one-year gain of 14%. BB&T Capital Markets and Sterne, Agee & Leach expect the stock to advance 24% to $15. Wabash shares have more than sextupled in 2010, earning investors a tidy sum. They jumped 75% in the past three months.

-- Written by Jake Lynch in Boston.

To see these stocks in action, visit the 10 Small-Cap Stocks That Tripled Portfolio on Stockpickr.


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