The billionaire founder of hedge fund Third Point startled many in entertainment today with the news that he has paid $1.1B for a 6.4% stake in Sony — and wants the company to create a stock for its movie, TV, and music businesses, selling as much as 20% to the public. But on Wall Street, where Daniel Loeb is an A-list celeb, the big surprises are that he showed any interest in showbiz — and that his language in the letter he sent to Sony was so polite. As a value investor managing more than $13B, Loeb, 51, likes to engage in deep research and then bet on relatively boring companies and assets that others overlook. Third Point’s most recent quarterly investor letter highlights its holdings in International Paper and mortgages, as well as John Malone’s European cable company Liberty Global. Although Loeb was raised in Los Angeles, the son of a lawyer and an historian, he’s known as a New Yorker. He earned an economics degree from Columbia University before he hit Wall Street. After working 12 years for firms including Citibank, Jefferies and Warburg Pincus, he founded Third Point in 1995 with about $3M from family and friends.

While Loeb has pals in Hollywood — he’s said to be close to David Geffen — he isn’t likely to join the parade of showbiz suckers who overpay for opportunities to hobnob with the stars. Still, he caught the industry’s attention last year when Third Point teamed with Deadline parent Penske Media Corporation in the acquisition of Variety. Loeb also put himself in the media spotlight with his sharp-elbowed campaign to oust Yahoo CEO Scott Thompson. That effort was far more in keeping with Loeb’s reputation as an activist investor who has little patience for executives and companies that seem to take shareholders for granted — and who speaks his mind without regard for the usual business niceties.  His “favored device is the scolding letter, formally addressed, publicly released, and ruthlessly frank in its assessments of managerial competence,” The New Yorker observed in a 2005 profile. In the Yahoo case, he accused the board of living in “an illogical Alice-in-Wonderland world.” He also disclosed that Thompson had misrepresented his academic credentials, noting that “CEOs have been terminated for less at other companies.” (Thompson ultimately resigned and was replaced by former Google exec Marissa Mayer.)Loeb is equally blunt in his libertarian political views, and support for Republicans. He told his investors early last year that “the unabated policies of a second Obama Administration would lead the country down an unsustainable path of exploding deficits and marginal private sector growth.” Early this year Loeb added his name to an amicus brief urging the U.S. Supreme Court to support gay marriage in the Hollingsworth v. Perry case.

Loeb’s letter this morning to Sony CEO Kazuo Hirai was courteous, but firm. He offered his proposals “in a spirit of partnership” — and added that he “would gladly accept a seat on Sony’s Board of Directors” so it can benefit from his experience and “sound advice on strategy and capital allocation, which we have brought to numerous public companies in the past.” Loeb had signaled his interest in Japan last month: He told investors that conservative Prime Minister Shinzō Abe’s decision to devalue the yen — part of an effort to rejuvenate the economy following the 2011 tsunami and Fukushima nuclear disaster — “amounted to a complete reboot of the Japanese monetary experiment” that would have a “far-reaching” impact. He told Sony today that as the government trims regulations “leading businesses like Sony … can spearhead this important growth.”

Loeb’s proposing the stock plan for Sony Entertainment as a way to raise cash that the company can use to reinvigorate its electronics businesses. The sale would enable Sony to “receive meaningful liquidity to inject into Sony Electronics while maintaining control” of the entertainment properties. It could “push down a meaningful but sustainable portion of its debt onto Sony Entertainment’s newly-created entity.” That would “reduce leverage at the parent company and provide much needed growth capital for Sony Electronics.”

Related: UPDATE: Sony Says Showbiz Units Not For Sale, But Welcomes “Dialogue” With Third Point