Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of small oil and gas companies are climbing double-digit percentages as oil moves higher today.

So what: Approach Resources (Nasdaq: AREX), Carrizo Oil & Gas (Nasdaq: CRZO), Clayton Williams Energy (Nasdaq: CWEI), Rosetta Resources (Nasdaq: ROSE), and Stone Energy (NYSE: SGY) have all jumped 10% or more today on the bullish move in oil. Oil is up 2.8% as I am writing and has reached a daily high of $86.10, more than $10 higher than its bottom less than a week ago. A few things are driving oil's move including slightly lower production from OPEC and a weaker dollar in trading today. But the biggest driver is less fear that our economic situation, and therefore oil demand, would get worse.

The price of oil hit bottom early last week on fears that Europe wouldn't be able to fix its financial mess and the worldwide economy may be headed for a further slowdown. But confidence came back to the market mid-week, and Germany and France have pledged to support European banks.

Now what: I'm not sure the fast and furious pace of the rise in oil prices will continue, but I think a slow and steady rise will help these stocks move higher in coming months. A few weeks ago, I wrote that the relatively low price of oil wouldn't last long because demand is still growing in emerging markets and oil supply is coming from more remote locations. If you agree with that assessment, these companies will be some of the biggest beneficiaries because of their leveraged return on the price of oil.

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