Google

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isn't usually thought of as ruthless.

And it's easy to see why. After all, the company was founded by two graduate students and is located on a colorful campus where Razor scooters and lava lamps abound. It chooses not to issue quarterly guidance and instead prefers to focus on idealistic missions like "organizing the world's information and making it universally accessible."

And it famously chose to include "Don't be evil" as a guiding principle in its IPO prospectus.

But a closer look at Google's dealings with partners and competitors reveals a company that is as brutally competitive as they come. Indeed, beyond the playful and fuzzy exterior, Google is as adept as playing hardball as any company in the modern era.

That's important for investors because it will be a key part of Google's ability to push beyond its core search market into new sectors where it will encroach on other companies' turf.

And when it comes to making deals, Google is as swift with the stick as it is with the carrot.

The latest example of Google's ability to fight dirty came this week, when the company announced a new platform that would allow developers to create applications for a variety of online social networks.

Called OpenSocial, the new platform is widely seen as a thorn in the side of popular social networking site

Facebook

, which had managed to attract a burgeoning community of developers to its own proprietary platform. The new platform "is going to forestall Facebook's ability to get everyone writing just for Facebook," a person with knowledge of the plans told

The New York Times

.

Google's move may have surprised some because the company was reportedly competing with

Microsoft

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to partner with Facebook in an advertising sales deal until only a few weeks ago. Facebook and Microsoft subsequently announced a deal in which Microsoft would make a $250 million investment in the social networking site and become the sole ad partner for the company.

Of course, it's no surprise that Google would counter Micorosft's move and come out with an alternative once it was passed up. But the rapid timing suggests that Google was working on a way to undermine Facebook -- even as it was in talks to partner with the company.

Far from the cheerful Google image, that sort of shrewd maneuvering is more likely to come from the likes of a company like Microsoft -- which is often criticized for its heavy-handed ways.

It's also likely to be noticed by future companies Google approaches for partnerships.

Still, the move makes sense given how Google sees partnerships as central to its strategy. Google has announced a spate of partnerships with mobile phone, media, and satellite TV companies over the years. The company is also known as a generous and deep-pocketed partner, as the three-year, $900 million deal it offered

News Corp.'s

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MySpace demonstrated.

And the flipside of being an open-handed partner comes in the form of being a brutal competitor. For those companies that choose to jilt Google, the flipside can often be a long, drawn-out and public process of retribution.

Take Google's dealings with

Viacom

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. The two companies had a high-profile falling-out at the beginning of the year after negotiations about how to share revenue for Viacom clips hosted on Google's

YouTube

video-sharing service broke down.

After pulling its clips from YouTube, Viacom turned around and slapped Google with a $1 billion lawsuit for copyright violation.

But despite proclamations at the time that YouTube's growth may be finished if Viacom pulled its popular clips, the video-sharing site has only continued to flourish. The number of unique visitors to YouTube grew from just over 30 million at the start of the year to about 47 million in September, according to research site Compete.com.

Now, it's Viacom, not Google, that seems to be coming around. "I suspect at some point in the future we'll work with Google," Viacom CEO Philippe Dauman told a conference in October, according to press reports.

That conciliatory statement comes not only despite an outstanding lawsuit, but also in the wake of an increasingly aggressive and personal tone taken by Google against Viacom. Not only was the suit against Google without merit, but Viacom's entire strategy is predicated on frivolous litigation, Google seemed to insinuate. "Viacom is a company built from lawsuits, look at their history," Google CEO Eric Schmidt said in July, according to press reports. "Look who they hired as CEO, Philippe Dauman, who was the general counsel for Viacom for 20 years."

Of course, it isn't surprising that Viacom wants to play nice. The company seems to have misjudged Google's potential when it came to video. Not only does YouTube's popularity continue to soar, but Google seems to have figured out a clever way to make money off videos and share it with partners through a new form of advertising.

Google's tough talk goes beyond mere posturing, though -- it also turns out to be good business. Given Google's emphasis on partnerships, it's important that it offers other companies as many incentives -- both positive and negative -- to fall in line.

Indeed, there are other reasons to believe that Google's approach may be paying off. Earlier this week, reports surfaced that Google was in talks with carrier

Verizon

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to collaborate on a mobile phone. The move struck many as odd given the recent animosity between the two companies.

Google and Verizon had locked horns on an upcoming wireless spectrum auction by the Federal Communications Commission. Verizon had sued the FCC after it adopted two of the suggestions Google had submitted for the auction, and Google had accused Verizon of trying to limit consumer choice.

Still, given Google's track record, Verizon may have shrewdly recognized that it's better to have Google as an ally than an enemy. And Google's tough stances in the past may have landed the company a friend in this case.