Is Shaq's next slam dunk an Internet start-up?

He's been called Shaq Daddy, the Big Shaqtus, Mayor McShaq and even Superman. Could four-time NBA champion Shaquille O'Neal's new nickname be the Venture Shaqitalist? (Tweet This)

That may be a stretch, but like so many big-time celebrities, O'Neal is trying his hand at start-up investing. The future Hall of Famer said on Friday that he's backing online investment site Loyal3 and joining the San Francisco-based company's advisory board.

Founded in 2008, Loyal3's mission is to democratize stock market investing. The company gives everyday investors, who want to put as little as $100 to work in emerging brands, access to initial public offerings. And it sells fractional shares of stocks, making it possible to buy a piece of Google for $10, as opposed to a single share for $535.

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It's also free for consumers, meaning no $9.99 transaction fees.

"I thought this was good for the common man, and Shaq is all about the common man," said O'Neal, who won NBA titles with the Los Angeles Lakers and Miami Heat, in an interview. "You don't have to be super rich to start out with Loyal3."

O'Neal, who declined to say how much he's investing in Loyal3, heard about the company during NBA's All-Star weekend in New York, from a friend who knows CEO Barry Schneider. O'Neal liked the idea, so he set up a breakfast meeting with the CEO.

They met for over two hours at the Ritz-Carlton hotel in Battery Park. As O'Neal was playing with the mobile app, a woman walked over and asked him what he was doing. To demonstrate, he bought a half-share of Apple on the spot.

"He said, 'Let me show you something that's going to amaze you,' " said Schneider. "And he bought stock in front of her."

Loyal3 makes money by acting as an underwriter on IPOs. The company works alongside the banks and gets an allotment of 5 to 10 percent of the offering to sell to its customers. Like the banks, Loyal3 gets a fee of about 7 percent. For example, if a company raises $100 million, Loyal3 could get $5 million worth of shares to sell, thus collecting revenue of $350,000.

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Loyal3 has participated in 13 IPO and follow-on offerings for companies including GoPro, AMC Entertainment and Santander Consumer USA.

Schneider said he was impressed with O'Neal's knowledge of the product and his overall tech savviness. O'Neal also serves as an adviser to Tout, a mobile video company that competes with Twitter's Vine service, and at the 2013 South by Southwest Interactive festival, he billed himself as the "world's tallest geek."

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There's an obvious benefit to having Shaq as a vocal supporter. He has almost 10 million Twitter followers and scores of fans across the sports, entertainment and music worlds. Schneider said O'Neal's ability to speak to millions of people that would otherwise be difficult to reach will make him a valuable adviser.

"I went to breakfast a fan of Shaq," said Schneider, who's actually a fan of the Golden State Warriors. "I left really excited about Shaq as a business partner."

As for O'Neal's new nickname, the big man said he's already come up with one: Shaloyal3.