Boy, how the times have changed! ExxonMobil (NYSE: XOM) the unquestioned king of the Big Oil jungle -- and the owner of a string of corporate earnings records -- has slid back to the land of the Lilliputians.

Of course, it wasn't unexpected. The likes of ConocoPhillips (NYSE: COP), BP (NYSE: BP), and Royal Dutch Shell (NYSE: RDS-A) have watched their earnings tumble in the most recent quarter, as crude oil and natural gas prices became shadows of their year-ago selves. ExxonMobil, which still has a market valuation that tickles $330 billion, saw its earnings slide by 58% during the most recent quarter, to $4.55 billion, from $10.89 billion a year ago.

And while the upstream (exploration and production) had been the star of the show for the past several quarters, it checked in for the March quarter with earnings of $3.5 billion. That number sounds impressive, but it was down from nearly $8.8 billion in the first quarter of 2008. Exxon's production was up on an oil-equivalent basis by 2%, liquids production was up about 7,000 barrels a day, and natural gas was down 34 mcfd year over year.

Beyond that, this was not a quarter where upstream strength offset downstream weakness, or vice versa. For the quarter, the company's downstream earnings were $1.13 billion, down slightly from a year ago.

As we consider Exxon, one significant (and too often ignored) issue regarding the company -- along with its operating successes -- is its cash situation. In the most recent quarter, for instance, capital and exploration expenditures were up 5% year over year to $5.8 billion. Cash flow from operations and assets sales totaled $9.1 billion during the quarter. Beyond that, the company spent about $9 billion for dividends and share repurchases, and Exxon is still sitting on $25 billion in cash.

But the real key for Fools is the way they should look at the company from an investment perspective. I hold to the belief that crude prices are likely to ascend slowly from their current levels. And while companies like Chevron (NYSE: CVX) and Total (NYSE: TOT) make for solid oil-related investments, it's hard to beat Exxon.

With its strong cash position, its solid technological capabilities, and its wide geographic spread, I believe ExxonMobil constitutes an excellent energy proxy for Fools looking to dabble in this still-relevant group.

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