"I'm not here to talk about Castro. You've got the wrong guy." Getty Images

Dallas Mavericks owner Mark Cuban entered New York's Stephen Wise Free Synagogue last night, mostly unnoticed by the very crowd of young Jewish professionals standing in line to hear him speak. After spotting his hosts on the other side of the room, Cuban politely weaved through the back of the crowd. Upon reaching the representatives from the Jewish Entrepreneurs Organization (JEO), who had organized the event, people began to recognize the mild-mannered billionaire, and one question hung over the room: "Really? Cuban's Jewish?"

In on the joke, the former Dancing with the Stars hoofer then gave his reasoning behind all the confusion: "It's because of my wonderful dance moves."

As he would reveal while addressing the crowd from the pulpit later, Cuban was one of only two Jews in his suburban Pittsburgh high school. But he was not Bar Mitvah-ed, choosing instead to play football in sixth grade. That decision was made about the same time as his first foray into the business world, when his father's poker buddies suggested he sell garbage bags door-to-door in order to bank enough cash to buy a new pair of basketball sneakers.

"Who would say no to a 12-year-old?" Cuban says.

From there, he went on to open a bar, which closed because he, like the majority of his clientele, was underage. And while it might be tough to explain how he went from a "really bad" employee of Mellon Bank to billionaire, he did offer this piece of advice:

"There's always a price to pay for risk. I don't invest in anything unless I know [it] really well or have a business interest," he said with a tinge of a Texas drawl. "Mostly, I put my money in municipal bonds."

That philosophy, of course, didn't apply to his purchase of the Mavericks, an investment he made because he thought he could run the organization better than its previous owner, Ross Perot. Cuban called himself the luckiest guy in the world and knocked the wooden table next to him. He doesn't want the spotlight on himself, as he later explained (his outspoken behavior towards David Stern to the contrary), and rarely put his name or face on charities to which he donates.

In fact, Cuban insisted he was just a regular guy. And at the meet-and-greet afterwards, he came across as the most patient, unassuming billionaire this side of Warren Buffet. He was more than happy to speak with every would-be tycoon who approached to hound him with business pitches ranging from investments in "peace between Israel and Palestine" to yet another Internet video site. Others, on the verge of tears, thanked him for his inspiring philanthropic work.

On the subject of sports, Cuban said he still doesn't know if the deal to acquire the Cubs will go through, that he'd trade for Jason Kidd again if he had the chance and that the reason he gets so riled up about the NBA is because the league puts its decision-making in the hands of guys who aren't businessmen (the referees).

When the topic of Josh Howard's recent faux pas during the national anthem at a charity football game came up, he had this to say: "Josh and I talk all the time. He was sorry he said it, it was a mistake, he apologized, we'll move on. When you live under the microscope sometimes flippant comments get you in trouble."

Cuban knows what it's like to have his own actions under constant criticism. When asked to take 20 seconds to show the crowd the classic Mark Cuban who acts out courtside at the American Airlines Center, the hard-nosed businessman emerged from behind the previously relaxed, folksy exterior. With a mock-glare, Cuban deflected the shot.

"Next question."