You won't find carbon-copied portfolios at The Motley Fool. True to our name, we encourage a range of investing opinions and try to analyze stocks from as many angles as possible. But in such a volatile environment, what stocks still stand out as screaming buys? Some of us decided to put our Foolish heads together to come up with a few great stocks for a variety of investing styles. Read on to find out what some of our staff picked as their favorites, and you might find that a little crowd-sourced Foolishness can go a long way.

John Reeves, writer/analyst
I feel that Google (Nasdaq: GOOG) represents a tremendous opportunity for investors right now. Despite being completely dominant in search, it's currently trading at a very reasonable valuation. And it's investing in a lot of fascinating projects that could prove quite valuable in the future. For example, the automated car could become a valuable asset for Google down the road (no pun intended). Finally, I really like what Larry Page has accomplished so far as CEO. Sure, he's a bit like Spock from Star Trek. But that may not be such a bad thing in our crazy world today.

Mike Klesta, online editor
In a word, energy. And I'm not just talking about oil, though a major oil player like ExxonMobil (NYSE: XOM) has the bona fides to make money even when oil prices are low. Natural gas will increasingly become a viable energy source. It's relatively cheap, abundant, and burns cleaner than any other fossil fuel -- a win-win-win in a world that needs to start paying more attention to climate change. So get on the bandwagon before it leaves the compressed natural gas station.

Paul Chi, analyst development program
Two of my favorite companies right now are Berkshire Hathaway (NYSE: BRK-B) and Markel (NYSE: MKL), both diversified holding companies led by top-notch value-oriented managers who excel at investing for long-term returns and have solid track records to boot. These companies aren't really secrets to anybody, but you wouldn't know it by looking at their historical valuations: They're at lower price/book multiples now than they've been in 17+ years. In the future, I expect these companies to trade at higher multiples of book value and for book value itself to grow at a healthy rate.

Rik Silverman, content experience designer
Occupy Wall Street is here to stay. A new emphasis on how business gets done and who profits will affect which companies -- and which of your investments -- thrive. Don't fall for fakers that spend money shaping their public image while neglecting their workers and badmouthing reform. Instead, check out Ethisphere's list of the world's most ethical companies. First, you'll see that this group beats the S&P 500 year after year. Second, you'll see plenty of Foolish favorite names, such as eBay, Adobe Systems (Nasdaq: ADBE), salesforce.com (NYSE: CRM), and many more. Stay on top of the trend by digging into these companies that are doing well and doing good.

Alex Planes, writer development program
I'm a big believer in technology's power to transform the world, and a lot of my favorite picks are based on a company's potential to do just that. That's why I like 3D Systems (NYSE: DDD) and iRobot. Both companies have technology that could change the way humans live, especially as they integrate more closely with modern lifestyles. After all, how cool would it be to print a wrench to fix your busted bike, or even to print out a whole new bike? It's not quite there yet, but complex functional objects should come from consumer-accessible 3-D printing within this decade. And if they're too big to be printed in one go, your trusty butler-bot could download the assembly instructions and put it together in a snap.

Foolish final thoughts
We've all got our own ideas and our own ways to value stocks, but that's what makes these opportunities so interesting. We hope you came away with an idea or two for your portfolio, but if you've got an even better stock idea, why not share it with us in the comments section below? We'd love to hear your thoughts.

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