Tumbling commodities prices have claimed a big victim. Ospraie Management is shuttering its biggest hedge fund after a 27% plunge last month, The Wall Street Journal reports, following a series of wrong-way bets on oil and natural gas, among others. The fund, run by Julian Robertson disciple Dwight Anderson has been selling off its holdings over the past three weeks, the paper reports. At its height last year, the fund had $3.8 billion in assets.

The Journal notes that the fund’s demise is another blow to Lehman Brothers (LEH), which holds a 20% stake in Ospraie. Lehman shares have lost 75% their value this year as the investment bank has been buffetted by bad bets on mortgage-related investments. According to reports Wednesday, Korea Development Bank has offered to take a 25% stake in Lehman for up to $5.3 billion, and reports out of the United Kingdom say the Tokyo Mitsubishi banking giant may also bid.

The Ospraie fund’s shutdown comes as the prices of many commodities have dropped sharply, and some investors suspect the fund’s selling has contributed to the plunge. But Philip Gotthelf of New Jersey trading firm Equidex says the commodities selloff could just be beginning, given how many investors rushed headlong into the sector during the past year or two. He tells Bloomberg television the price of crude oil could be on its way to $50 a barrel from a recent $108.

Airline stocks surged Monday as investors rejoiced at the latest decline in oil prices. Among the big gainers were UAL (UAUA), parent of United Airlines, which rose 17%, along with AMR (AMR), parent of American, up 12%, and Continental (CAL), up 9%. The rally came after Morgan Stanley analyst William Greene said the a decline in crude oil’s price to $115 from last month’s high at $147 “is a game-changing event” if it holds.

Despite the relief on the energy front, all isn’t well at United. Its pilots union called Monday for CEO Glenn Tilton to resign, saying that under his tenure United “has gone from being the finest airline in the world, with the best route structure and safety record, to a shell of its former self.”

The union notes that the airline ranked next to last in on-time arrivals and last in misplaced baggage in the latest U.S Department of Transportation survey. Meanwhile, the company’s shares have lost more than two-thirds of their value since United emerged from bankruptcy protection two-and-a-half years ago.

“This is not a personal attack on Glenn Tilton,” the union said in a statement. “These dismal numbers speak for themselves. They are a reflection of his inability to lead, his incompetence as a manager and his failure in virtually every category that can be measured.”

Update: United calls the union’s claims “an obvious and predictable attempt to deflect attention from ALPA’s illegal activity cited in our lawsuit, which details the organized and concerted effort to harm our customers, our employees and our performance.” United last month sued the union, claiming it organized a sick-out that forced the airline to cancel hundreds of flights, costing it millions of dollars in profits. United said Monday that the pilots’ campaign against Tilton “is part of the union’s ongoing two-year campaign to intimidate United into reopening a contract that runs through December 2009.”

British oil giant BP (BP) got a reminder Tuesday of the high cost of doing business in a country that’s generally suspicious of the West. To wit: the foreign staff of TNK-BP, a Russian joint venture half-owned by BP, was told Tuesday morning that some would face “temporary relocation” because Russian authorities won’t renew their work visas. In an e-mail to employees, BP CEO Robert Dudley described the situation as “most unfortunate and harmful to our company,” reports the Financial Times.

The visa snafu could force all of TNK-BP’s foreign staff, including Mr Dudley and other senior executives, to leave the country by the end of the month. TNK-BP was formed in 2003 by merging BP’s Russian oil and gas assets with the oil and gas assets of Russia’s Alfa and Access-Renova Group. BP stock was down about 2% in New York Stock Exchange trading following the news.

The ruling is the latest twist in the struggle between BP and Russia to control the joint venture, says the FT. If Dudley and other executives leave, it will leave operational control of the company in the hands of their Russian partners. In the past, BP has accused its partners of corporate raiding. People close to the company tell the paper that Russian shareholders are looking to sell TNK-BP to a state-owned company such as Gazprom or Rosneft. Russian shareholders deny they want a sale.

Exxon Mobil’s (XOM) latest numbers continue to draw scrutiny. Exxon posted a 17% rise in first-quarter earnings, to $10.9 billion, or $2.03 a share, as the company benefited from the rise in energy prices. But shares fell 3% in afternoon trading, as the numbers missed Wall Street’s expectations and investors worried about an unusual production decline. Sen. Hillary Rodham Clinton indicated in an afternoon statement from her presidential campaign office that she’s enraged by the implication of Thursday’s selloff - that Exxon isn’t making enough money.

“There is something seriously wrong with our economy when Exxon’s record $11 billion in quarterly profits are seen as a disappointment by Wall Street,” Clinton said. She went on to use the company’s latest gains to reiterate her call for a gas tax holiday — a proposal has been criticized by economists who say it won’t result in lower prices for consumers. “I believe we should impose a windfall profits tax on big oil companies and use that money to suspend the gas tax and give families relief at the pump,” Clinton said.

While Clinton rails about Exxon making too much money, others are wondering if the company isn’t actually doing things that have the effect of trimming profit numbers at a politically sensitive time. Robbert Van Batenburg, head of global research at brokerage firm Louis Capital Markets in New York, points to the growing gap between Exxon’s cash flow from operations and its net income.

While investors generally expect to see broadly similar trends in those numbers, Van Batenburg notes that Exxon’s latest quarter showed a 50% jump in cash flow, to $21.4 billion, but only a 17% rise in net income. In the fourth quarter, the gap was smaller: Back then, Exxon posted a 28% rise in cash flow from operations, to $11.3 billion, and an 18% rise in net income excluding special items, to $11.7 billion.

Where’s all that cash flow going if it isn’t flowing into earnings? Capital spending — up more than 30% in the latest quarter, to $5.5 billion — is one beneficiary, says Van Batenburg, who doesn’t own the stock and doesn’t believe the company is doing anything untoward with its books. Indeed, the company has of late been criticized for failing to keep pace with rivals such as Shell (RDS.A) and BP (BP) in its investment spending.

With Exxon shares trading near an all-time high even after Thursday’s decline, Van Batenburg views the latst quarter as part of an effort to sidestep what he calls a “backlash” against energy-company profits. “If I were Mr. Tillerson I’d do the same thing,” he says, referring to Exxon’s CEO.

Hundred-dollar-a-barrel crude doesn’t necessarily lead to gushing profits, as oil refiner Valero (VLO) is showing. The San Antonio-based company warned late Monday that its first-quarter earnings will fall far short of Wall Street’s expectations, as margins on gasoline and other products narrowed and unplanned refinery outages hit the bottom line to the tune of $400 million. Valero expects to make just 10 to 35 cents a share for the quarter ending this month - down from $1.86 a share last year and below the 91-cent analyst estimate.  CEO Bill Klesse is scheduled to appear Wednesday afternoon at the Citi Refining Conference in New York to discuss the business’s fundamentals. With Valero shares falling early Tuesday and approaching a 52-week low, he may be fielding some tough questions.

Oil isn’t the only commodity whose rise is setting off alarm bells. Just a week after crude oil touched $100 a barrel for the first time, gold set a record high at $876 an ounce, Bloomberg reports Tuesday. The surge comes as investors worry about slowing growth and rising inflation, a combination commonly termed stagflation but recently given other names as well. Also fueling the rise of oil and gold is the decline of the dollar, which continues to drop amid worries that the U.S. may slip into recession. The recession debate remains far from settled, though there are indications that even if the economy continues to grow modestly, things could get hairy.

Tired of hearing about hundred-dollar-a-barrel crude oil yet? Get ready for $200 crude. Bloomberg reports that options traders at the New York Mercantile Exchange are making a big bet that crude prices will double from recent levels to hit $200 by year end. The price of the option contracts has risen 36 percent since last month as investors seek a cheaper way to profit from the rise of oil prices than the typical futures market trading, Bloomberg notes. Supporting this bet is the widely-held observation that the world’s supply of petroleum is not keeping up with strong growth in demand. That notion has one investment banker pointing out to Bloomberg that, even at recent prices, crude oil is cheap going by certain unconventional measurements. “One hundred dollars a barrel is actually 14.9 cents a cup,” notes Matthew Simmons of Simmons International. Drink up, drivers.

The price of crude oil hit $100 a barrel for the first time ever Wednesday, reflecting the usual worries about diminishing production and increasing demand. The move, which builds on a 57 percent rise in oil prices during 2007, comes on the same day that Goldman Sachs (GS) analysts predicted prices of commodities such as corn and soybeans will continue to soar in 2008.

So how to cash in if oil prices keep rising? Jimmy Rogers says buy other commodities, such as sugar and cotton, Fortune’s Brian O’Keefe reports. At RealMoney.com, Jim Cramer says buy agricultural names such as Deere (DE), which nearly doubled last year, and Mosaic (MOS), which with a 342% jump was the biggest gainer last year in the Fortune 500. Despite all the usual worrying about high gas prices weighing on consumer spending, there is one good thing about the price of oil hitting triple digits: It gives editors renewed license to trot out the term ”psychologically important.”

Oil prices spiked Wednesday, reversing their recent decline. The Nymex-quoted price for a barrel of crude oil jumped 5 percent, rising $4.37 to $94.39, after the U.S.  said inventories fell for a fourth straight week. Analysts said the Fed’s efforts to stimulate economic activity by lowering interest rates may have fed Wednesday’s run-up, by reducing chances of a demand-squashing recession. “The Fed is putting the sizzle back in all the markets,” an analyst told CNNMoney’s Steve Hargreaves. The spike came after Goldman Sachs boosted its 2008 oil price target to $95 a barrel, saying that even if demand does fall in a U.S. slowdown, producers will respond by limiting supply. Further building the case for higher prices, The Wall Street Journal reported that Saudi industrialization efforts mean there will be less oil for importers like the United States. That’s not a welcome thought.

Here come the petrodollars. On the heels of this week’s investments in Citi (C) and Sony (SNE), Middle East entities are going to be kicking the tires on U.S. media properties, Liz Rappaport writes at TheStreet.com. She reports that real estate investment firm Blumberg Capital Partners is raising $500 million from investors in the Middle East for a fund that would target newspapers, movie studios, online media outfits, broadcast news and possibly radio businesses. The interest is fueled in part by the piles of dollars flooding places like Dubai and Abu Dhabi as oil prices near $100 a barrel. By way of comparison, David Wessel notes at The Wall Street Journal that the Abu Dhabi Investment Authority’s $7.5 billion investment in Citi amounts to the proceeds from a single week of U.S. oil imports. “Given that foreign dollar reserves eventually have to come home,” Michael Shedlock writes of the Citi deal, “this deal is just a token down payment for what’s to come.”