Yesterday, as the Dow continued its 512-point drop, we spent four-and-a-half hours chatting live with concerned Fools. Many requested a few simple ideas for opportunities worth seizing amid this market sell-off. We solicited six compelling candidates from Motley Fool advisors, analysts, and editors -- and our CEO.

Tom Gardner, Motley Fool co-founder and CEO, and Stock Advisor co-advisor:
If you believe that the U.S. is headed back into recession, and you believe that our political officials won't see the light on the critical need to both close tax loopholes and ratchet back spending, then you'll naturally want to take your portfolio into a more defensive stance. But how? I recommend looking for companies with these six traits:

  1. Easy access to capital (their own!)
  2. Substantial future opportunities in foreign markets
  3. A stellar history of operating results
  4. The reputation of being a cost-saver for consumers
  5. World-class leadership
  6. A steady dividend

This is why my recommendation is a core stock holding of mine in our Stock Advisor service: Costco (Nasdaq: COST). 

Jeff Fischer, advisor, Motley Fool Pro and Motley Fool Options:
Waste Management (NYSE: WM) has been thrown into the trash heap over the last month, declining from $38 to $30 on weak trash volume. The country's landfill leader and largest recycler now pays owners a 4.5% dividend. Although competitors are lowering prices to haul away your trash, as a landfill owner, Waste Management still benefits by charging these competitors to use its resources. Earnings estimates for 2012 were just lowered, but the stock trades around a reasonable 12 times consensus estimates. Although recessions lead to lower trash volume, this business should be able to sort through it and come out smelling stronger.

Eric Bleeker, Fool.com technology editor:
I like cheap stocks, but I love "are you kidding me?" cheap stocks. After sliding nearly 18% in the past two weeks, EMC (NYSE: EMC) is approaching that territory.

True, the stock still trades at 25 times earnings. However, that metric conceals EMC's 80% stake in virtualization kingpin VMware (NYSE: VMW). Netting out that holding, and removing VMware's contributions to EMC's financials, you'll find that EMC trades for only around seven times trailing free cash flow. That's a bargain-basement price for a company that's a proven leader in the storage industry -- one of the tech sector's hottest growth areas. Even if you're less optimistic on cloud computing and VMware's position in it, giving EMC credit for half of VMware's current value leaves EMC trading at 13 times cash flow.

If the market rout continues, EMC's a great way to buy an industry-leading company with very high upside potential. This is one deal I won't be passing up.

David Williamson, Fool.com health-care editor:
Suffering from feelings of anxiety, insomnia, and even depression when watching the markets?  Bristol-Myers Squibb (NYSE: BMY) has the medicine you need. Health care is often considered a safe sector in tough times. It's unsurprisingly outperforming so far in 2011, and among big pharma stocks, Bristol-Myers is the clear standout.

The market doesn't appreciate the potential of the company's pipeline. Although the "patent cliff" is set to do a number on earnings across the industry, recent Bristol-Myers successes including Yervoy and atrial fibrillation frontrunner Eliquis will allow the company to absorb the loss of top-selling drug Plavix better than Eli Lilly will weather losing its top drug, Zyprexa. So while earnings may tread water in the short term as Bristol-Myers transitions to new products, this stock tops its sector for long-term potential. And while you're waiting for that growth to fully kick in, you'll enjoy a substantial dividend yield of 4.7%. 

Buck Hartzell, director of analyst learning:
Over the past 12 months, White Mountains Insurance (NYSE: WTM) has handily outperformed the S&P 500. Yet even at just more than $400 per share, White Mountains is far from its summit. In May 2011, it agreed to sell Esurance to Allstate for a cool $1 billion. This transaction should add $80 to reported book value per share.

With that adjustment, White Mountain's book value will reach a lofty $530 per share. Don't let the high altitude of the absolute stock price scare you off -- this thing is trading hands at only three-quarters of its own book value. The chairlift is leaving the station, so don't miss it this well-run, cash-flush business.

Brian Richards, Fool.com managing editor:
I'm going to cheat a little bit and give an exchange-traded fund rather than a stock: Vanguard Dividend Achievers (NYSE: VIG). This low-cost ETF, with an expense ratio of just 0.18%, is suitable for conservative investors. It comprises 127 companies that have increased their regular annual dividend payments for at least 10 consecutive years. The ETF offers exposure to high-quality large-cap names, and allows nervous investors to sleep better. Roughly 61% of the holdings represent traditionally defensive industries: consumer staples, industrials, and energy.

The fund's top 10 holdings, which alone make up 40% of assets, are a who's-who of dividend-paying blue chips: stocks like McDonald's, IBM, and Coca-Cola. At just more than 2%, the ETF's yield isn't overwhelming, but remember: Those payouts should grow over time.

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