The biggest names in the investing world have the gravitas to move stock prices with as little as a word. And two of the industry's biggest guns, David Einhorn and Bill Ackman, are presenting their top long or short ideas at next week's Value Investing Congress. Einhorn has made a big name for himself over the past couple of years, wowing the crowds with intensely detailed short cases on Florida real estate play St. Joe and Green Mountain Coffee Roasters.

The world is waiting to hear what these heavy hitters have to say. That's why we're attending in New York and will be covering the goodness here on Fool.com. We've got our guesses at the most important themes of this year's congress, but here are some specific stock ideas we think the gurus might talk up.

Joe Magyer, Inside Value: I'm betting at least one of the biggies at the VIC will talk up ways to play spiking interest rates -- a contrarian play that could raise the tide under the boats of discount brokerages like TD AMERITRADE (Nasdaq: AMTD), which lends to aggressive investors who use margin to juice their returns and also collects a portion of clients' assets in money market accounts. The stock is a personal favorite that I recently recommended Inside Value members double down on.

Another favorite could be General Motors (NYSE: GM). The stock is down 28% since its IPO almost two years ago because the European segment is a hot mess, questions linger about the health of the U.S. recovery, and Uncle Sam's refusal to sell his stake at a loss has cast a pall over the stock, brand, and business. Sales have grown 15% since the IPO, though, and posted a profit each quarter since rising from the ashes of bankruptcy. It has also cut costs, taken steps to lighten its pension burden, stopped leaning on discounts to move product, and has a slate of new vehicles on the way poised to breathe life into sales. The stock is selling for 6.2 times analysts' estimates of 2013 earnings, to top it all off, which makes it sufficiently cheap, contrarian, and dirty enough for a VIC presenter to chase after.

Bryan Hinmon, CFA, Motley Fool Pro: Value investors have been banging the bank bargain bongos for some time now, but investors remain wary. The reason? Heightened regulation has increased costs and restricted participation in some business lines, forcing banks to remold their operations and figure out new ways to earn high returns on equity. Companies that help banks focus on their core businesses and shed noncore functions could be the key to making those bank bets pay off -- but investors still have to choose the right bank to bank on.

An easier case can be made for Broadridge Financial Solutions (NYSE: BR), which has flown under the radar since its spinoff fromAutomatic Data Processing in 2007. Its growing operations-outsourcing business is helping banks shed cost centers (for example, by lightening their back-office staffing and investment requirements) and instead focus their attention on revenue-generating activities. Broadridge is able to invest in its outsourcing offerings because of the consistent cash flow thrown off by its near monopoly in the proxy solicitation business. It is also able to win business because its financial strength gives banks confidence that Broadridge can withstand financial and economic turmoil. For Broadridge, those deals mean multiyear recurring revenue streams. Value hounds D.E. Shaw Investment Management and Third Avenue Management have already taken note, but the Broadridge story has plenty of pages left to turn, with shares only trading at 10 times free cash flow.

Michael Olsen, CFA, Motley Fool Special Ops and Million Dollar Portfolio: Talk of inflation -- in commodities and food, in particular -- has been a hot potato amid the QE Infinity. But amid a historic drought, concerns over sputtering Asian giants, and a world economy that hangs in the balance, PotashCorp (NYSE: POT), the world's largest producer of potash fertilizer and a leading producer of phosphate and nitrogen, looks dirt cheap, at 15 times my estimate of trailing cash flow. It and two other dominant potash producers, Agrium and Mosaic, form what's affectionately called "the cartel," one of two potash oligopolies that negotiate potash prices collectively, ensuring an evenhanded approach to supply expansion and enviably high margins.

Though the near-term's a bit iffy, PotashCorp has the wind at its back. Global consumption of proteins, fruits, and vegetables is poised to continue growing. Cattle, in particular, require a lot of feed grain, and exponentially higher use of fertilizer. According to a recent Tyson Foods presentation, a pound of chicken requires two pounds of grain, and a pound of pork and beef require 3.5 pounds and seven to nine pounds, respectively. And despite a fairly rapid, recent increase in protein consumption, one country's been conspicuously absent from the party: India. With a population of more than a billion, at 2010's end, its per capita protein consumption was just about a a seventh of China's.

Add investments in Sociedad Quimica y Minera, Israel Chemical, Arab Potash, and Sinofert worth about 25% of its market cap before taxes -- whose value the market doesn't seem to fully appreciate -- and PotashCorp starts to resemble that rare, wonderful confluence of growth and value.

Joel South, Fool.com energy editor: "Buy when others are fearful" is a mantra often repeated by value investors. That's easy enough on paper, but the best identify industries facing significant headwinds in the short term, and plow down to find the hidden gem in the heap. Investors have deserted anything natural gas. Advances in horizontal drilling and improved hydraulic fracturing, an uncharacteristically warm winter, and a drill-at-any-cost mentality (among producers) contributed to a huge supply glut, and accordingly depressed gas prices. With the differential between oil and natural gas increasing, so too are the opportunities to purchase deeply discounted companies.

Firms like Devon Energy (NYSE: DVN), with its currently natural-gas-heavy production mix and strong balance sheet, are positioned to ride out the ugly and benefit as natural gas prices turn higher. And for Devon, the future looks much brighter: It possesses a nice mix of oil and gas properties (which the market seems to have missed), long-term leases, a returns-focused management team, and growing exposure to oil. That's a mix most any value investor can appreciate.

We'll be posting our analysis of the latest and greatest from the congress next week, so stayed tuned to these pages.

If the idea of seeing Bill Ackman and David Einhorn in the flesh is just too tempting, feel free to join us. Motley Fool readers can attend the Value Investing Congress with a $300 discount. Click here to learn more, and be sure to enter the discount code FOOLN12.

Joe Magyer; Bryan Hinmon, CFA; Michael Olsen, CFA; and Joel South all contributed to this report.