Most of us would be thrilled to invest in a stock that doubles our money, but it certainly isn't easy to find these stocks. According to data provider Capital IQ, in the last year only 1.4% of 6,700 stocks trading on the U.S. exchanges were able to double their price.

BusinessWeek started hunting some of these potentially great stocks by asking fund managers to choose those firms expected to provide 100% returns in the next few years. Of course, the resulting list is by no means a sure thing, since major factors such as the ongoing credit crisis and challenging market conditions could affect results in unpredictable ways.

But let's look at some of the strategies used when picking high-potential stocks.

Mary Lisanti, portfolio manager at the Adams Harkness Small Cap Growth Fund, focuses on young companies in the small-cap segment. She points to stocks like Rubicon Technology (NASDAQ: RBCN) and Titan Machinery Inc. (NASDAQ: TITN), saying that investors can have a big advantage when they recognize potential before the market does.

MOST NOTEWORTHY: National City, Syntax Brillian and Medco Health were today's noteworthy upgrades:

• Deutsche Bank upgraded shares of National City (NYSE: NCC) to Buy from Sell on valuation as they believe their $9.00 target is in-line with the company's franchise value.
  
• Baird upgraded Syntax Brillian (NASDAQ: BRLC) to Outperform from Neutral based on recently announced strategic initiatives and valuation.
  
• Jefferies upgraded shares of Medco Health (NYSE: MHS) to Buy from Hold as they believe the company's renewed PBM contract with United Healthcare (NYSE: UNH) removes a major overhang.

OTHER UPGRADES:

• Friedman Billings raised Downey Financial (NYSE: DSL) to Market Perform from Underperform.
  
• Volterra (VNASDAQ: LTR) was raised to Buy from Neutral at Piper.
  
• Alliance Data (NYSE: ADS) was raised at JP Morgan to Overweight from Neutral.

MOST NOTEWORTHY: Today's noteworthy upgrades include ConAgra Foods, Inc (CAG), Dell Inc (DELL), Ryland Group, Inc (RYL) and Volterra Semiconductor Corp (VLTR).

• Prudential upgraded shares of ConAgra Foods Inc (NYSE: CAG) to Neutral from Underweight with a $26 target on valuation.
• Pacific Crest upgraded shares of Dell Inc (NASDAQ: DELL) to Outperform from Sector Perform as the firm believes new management, new products and supply chain cost realignments could boost operating margins.
• Ryland Group, Inc (NYSE: RYL) was upgraded to Neutral from Underperform at Credit Suisse.
• Unterberg upgraded shares of Volterra Semiconductor (NASDAQ: VLTR) to Market Perform from Underperform on valuation.

OTHER UPGRADES:

• Friedman Billings upgraded Peabody Energy Corp (NYSE: BTU) to Outperform from Market Perform based on lack of CAPP exposure, growth profile, rising international demand and certain benefits from the scrubber trend.
• JP Morgan upgraded shares of Cincinnati Bell Inc (NYSE: CBB) to Overweight from Neutral, as the firm believes higher capex is reflected in the valuation and FCF should recover in 2008.
• Sandler upgraded First Charter Corp (NASDAQ: FCTR) to Buy from Hold based on valuation.
• Brean Murray has increased confidence in the success of Isle of Capri Casinos' (NASDAQ: ISLE) Isle casino, soon to open at Pompapno Park, and the considerable option value that should be embedded in shares related to a Florida gaming bill which would loosen restrictions on gaming at pari-mutual facilities. The firm upgraded shares to Buy from Hold on the news.
• Deutsche Bank upgraded shares of Pogo Producing Co (NYSE: PPP) to Hold from Sell to reflect the likelihood of corporate action over the near term, most likely the sale of the company in whole or in parts.
• Merill Lynch upgraded Janus Capital Group Inc (NYSE: JNS) and Calamos Asset Management, Inc (NASDAQ: CLMS) to Buy from Neutral.

Analyst summaries provided by TheFlyOnTheWall.com (subscription required).

MOST NOTABLE: Cabela's Inc (CAB), Time Warner Inc (TWX), Open Text Corp (OTEX) and Tortoise Capital Resources Corp (TTO) were some of today's more notable initiations:

• Cabela's inc (NYSE: CAB) was initiated with an Outperform rating and $30 target. The firm is confident in Cabela's outlook given the company's substantial store expansion opportunities, encouraging operating environment and valuation.

• Time Warner (NYSE: TWX) was started with a Buy rating and $25 target at UBS.

• Benchmark initiated Open Text Corp (NASDAQ: OTEX) with a Sell rating.

• Tortoise Capital Resources (NYSE: TTO )was initiated by both Ferris Baker and Stifel with a Buy rating.

OTHER INITIATIONS:

• CIBC initiated Volterra Semiconductor Corp (NASDAQ: VLTR) with a Sector Performer rating.

• Goldman initiated Savvis, Inc (NASDAQ: SVVS) with a Buy rating and $50 target.

• Cowen started Cogent Communications Group, Inc (NASDAQ: CCOI) with an Outperform rating.

• Avondale initiated Callaway Golf Co (NYSE: ELY) with a Market Outperform rating and $20 target.

• ThinkEquity started Adventrx Pharmaceuticals, Inc (NYSE: ANX) with a Buy rating and $5 target.

Analyst summaries provided by TheFlyOnTheWall.com (subscription required).

MOST NOTEWORTHY:

• International Business Machines (NYSE: IBM) was upgraded to Buy from Sell at ThinkEquity citing increased performance and profitability in the company's Global Service unit and strong software sales; IBM's target was raised to $110 from $70.

OTHER UPGRADES:

• Volterra Semiconductor (NASDAQ: VLTR) was upgraded to Strong Buy from Buy with a $21 target at First Albany. The firm told clients Volterra's innovative power management technology is driving market penetration in higher volume markets while driving down costs per amp.

Analyst summaries provided by TheFlyOnTheWall.com (subscription required).