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 NetSpend Holdings (Nasdaq: NTSP) initially surged more than 11% only to fall back to up 2% as of this writing. A rally in shares of peer Green Dot Corp. (Nasdaq: GDOT) may account for the gains.

So what: The rally is a rarity for both companies, which have suffered tough losses year to date. Shares of Green Dot have twice plunged more than 10% over the past month. Volatility, thy name is stocks in the prepaid banking industry.

Now what: For those willing to stomach the occasional bumps and bruises, there does appear to be a genuine -- perhaps even Rule Breaking -- opportunity here. NetSpend and Green Dot serve a base of some 60 million Americans who don’t have access to classic banking services.

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