The markets remain mixed as the big indexes essentially flip-flopped from their Monday close. Retail sales came in better than anticipated, but despite totally reversing course, up 0.8% versus June's 0.7% decline, it still couldn't get investors excited. Of course, talk that Greece is looking for a two-year austerity extension threw a wet blanket on any enthusiasm. Tomorrow's inflation data could move the markets, but August tends to be a slow month, so all but the largest headlines may fail to find traction.

The Dow Jones Industrial Average (INDEX: ^DJI), finished up just 2 points, or 0.02%, the near definition of flat -- but not to be outdone, the S&P 500 managed to move only 0.01% to the downside. The Nasdaq was our heavy lifter today, losing an incredible 0.2%. Feel the volatility!

On the Dow, we saw a large 3.6% gain from Home Depot (NYSE: HD), which not only beat estimates but raised guidance as well, giving investors confidence that the housing recovery will continue. Bank of America (NYSE: BAC) shares, meanwhile, were up 0.8% on no real news, but the stock continues to be a favorite among traders. Today alone, 104 million shares traded hands, the most of any stock on or off the Dow, but amazingly that's still significantly under the company's three-month average volume of 160 million shares. If you are thinking of investing in B of A, make sure you're prepared for the daily volatility that comes with its current status.

The biggest gainer on the Nasdaq was Arena Pharmaceuticals (Nasdaq: ARNA), closing up 15% on talk that Big Pharma was stalking the small biotech as a takeover candidate. Arena already has a marketing deal with Eisai, but that isn't enough to scare off a motivated buyer. I would be slightly surprised if Arena, or for that matter, its competitor VIVUS (Nasdaq: VVUS), which rose on the news, get taken out before a would-be acquirer can see how doctors are prescribing their respective drugs. Sure, it will cost more at that point, but I would rather pay a premium for a good product than get a deal on a dud.

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