Analysts say that many of Google's far-reaching plans are at least 10 years out and won't likely impact its stock until it reaches "the point at which that business [segment] hits the billion-dollar revenue mark," according to Sawhney. "That's when it starts to become relevant."
Ironfire Capital hedge fund founder Eric Jackson, who holds no position in Google, said, "Even though everyone is sort of excited about driverless cars, it's hard to take that technology and put a price on it and build it into your model about what Google should be worth today."
Nest may be the best short-term bet among all of Google's new long-term and far-flung ventures. Topeka Capital's Anthony says sales of Nest units may have the biggest, tangible stock impact over the next few years.
The Google of things
Melissa Schilling, a professor of management and organizations at New York University's Stern School of Business, points out how Google's Nest endeavor is likely a way to extend the Internet of Things to where we live, using artificial intelligence to make our interaction with things in our homes easier and smarter. "It's not the utility they were after—there are lots of home automation solutions—it's the interface with your home," she said. "It's how you make your home interact with you in a way that's less cumbersome."
Ironfire's Jackson said that Nest also represents potential ad dollars. "It's very easy to imagine how Google's core ad business is going to be further supported by knowing just that much more about you and your personal life," he said. "Nest is layering on that much more information to better understand you and which ads to show you."
The technology that powers Google's driverless cars may also fall along these lines "as cars become information portals on wheels," said Kellogg's Sawhney. Google will probably license the technology to automakers, removing the immense risk of becoming a carmaker itself.
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For the long term, it helps to view Google and its new ventures through another lens: a company searching for new on-ramps to the Internet. "The first thing to look at is how do you define the core competency," Sawhney said. "From that standpoint, online search is not as Google would define itself—it takes a much broader view of how it thinks about its business, organizing the world's information as useful and monetizing that process." He added, "Google wants to own all of these on-ramps."
Charles O'Reilly, a professor of management at Stanford's Graduate School of Business, called these distant Internet-related projects a form of organizational ambidexterity—the ability of a company to manage its current business while simultaneously preparing for changing conditions, even if it means moving in a somewhat different direction. "When companies are doing well, that's when they should be experimenting," he said, citing Goodrich Corp., the former tire company now entrenched in aerospace, and Nokia, which started out as a paper mill. "This is not random, it's not unrelated diversification; you only want to do this if the mother ship has some capability that it can leverage to its advantage in the new business."
Google's move into wind and solar—the company recently made its fifteenth investment in renewable energy, pouring $75 million into the Panhandle 2 wind farm in northern Texas—makes a little less sense to B school professors looking at future revenue diversification schemes. "That's probably a pet project, an idealistic ambition from someone who is aiming to solve one of the world's biggest problems," said NYU's Schilling. Google thinks it makes sense as one of the world's largest consumers of energy.
And Google's off-the-path ventures—which could go beyond Enderle's worry of a "self-driving car rolling over a line of kids waiting for a school bus"—is a strategy that equity analysts think about as a compelling options portfolio in a volatile industry where no one's exactly sure what's next.
"[Google is] probing a lot of random veins; they don't quite know the outcome or what the return will be," said Kellogg's Sawhney. "But when a company is as large and as innovative as Google is, it can afford to make mistakes and do experiments."
Given Google's massive toehold in its core moneymaking market, analysts say the company isn't yet betting the farm. "It's not like [Tesla Motors co-founder] Elon Musk building a big factory and hoping that he can sell enough cars to pay it off—none of Google's moves are costly enough to threaten the cash cow," said NYU's Schilling, noting that by not just doubling down on search, Google is making sure it will be around no matter in what direction the world will shift.
"But if we start to see lots of big acquisitions in other areas, that would make me very sad and definitely erode what I see as its core value," said Schilling.
—By Maggie Overfelt, Special to CNBC.com