That's when the newly minted millionaire decided to switch things up. "I started trading technology stocks — I did so well I turned that into a hedge fund and almost immediately sold that," he said on an episode of GQ's YouTube series "Actually Me," in which he went undercover on the internet and responded to real comments from Twitter, Reddit, Quora and YouTube.
Cuban moved to Los Angeles "to live on the beach and just be retired."
In LA, he signed up for acting classes as a way to meet people but decided to put his new skills to test and started auditioning for commercials. "I had to put the Taco Bell hat on and just act stupid," he recalled. "I did some Ford commercials."
He even tried to get on the big screen: "I auditioned for the movie 'Twister' and got a callback."
Cuban, who was trying out to be the character Dusty, an enthusiastic storm chaser, ended up getting a second callback for the 1996 drama. But the casting team eventually selected the late Philip Seymour Hoffman for the role.
Hoffman, who would go on to be nominated for four Academy Awards throughout his career, was "mis-cast," Cuban joked. "I was right for the role."
Cuban's acting stint didn't last long. A few years after the 1996 audition, he co-founded a company called Audionet, which became Broadcast.com. During the dotcom boom, it grew to over 300 employees and in 1999 was acquired by Yahoo for $5.7 billion, making Cuban a billionaire at age 40.
Cuban, who now stars on "Shark Tank" and owns the Dallas Mavericks, never made it in Hollywood, but he wouldn't change anything about his career path.
"Never stop learning. Never stop grinding," he advises young people just starting out their careers. "Never stop loving every single minute of your life."
Like this story? Subscribe to CNBC Make It on YouTube!