If you happen to be in Missouri, keep an eye out for a commercial on cable TV featuring a guy in white tights and a green cape. His name is Brian Laoruangroch, and he is the 24-year-old founder and CEO of Green Mobile, a company that buys, sells, trades, and repairs used mobile phones.

The business started in 2004 basically as an eBay hobby, when Laoruangroch realized he could buy old phones and resell them for a profit. He soon built his own website to market refurbished phones; his brother Brett, like Brian a University of Missouri student, joined him and took charge of learning how to repair them. They eventually opened a kiosk in a local mall, and then, last summer, Laoruangroch decided the business was large enough to support a retail storefront in Columbia. He borrowed money from his parents and then landed a $50,000 bank loan backed by the Small Business Administration -- no small feat for any business, let alone one run by an undergrad. Along the way, he pumped money into Green Mobile by doing side work as an actor and model in Kansas City. When it came time to decide whether to open a second retail location there, Laoruangroch had to make a tough choice: Keep his car or sell it to raise money to open a new store? In the end, the car had to go.

The company has passed the $500,000 mark in revenue, and Laoruangroch is learning about the difficulties of hiring and managing employees. At one point, Green Mobile's head count was up to 30, which Laoruangroch found too difficult to manage. He trimmed the staff by half. His new philosophy about managing: "You can get a lot more done with a staff of 14 who care than with 25 or 30 people who don't."

Advertising has come naturally to the founder, who drew on his acting experience to make a series of kitschy TV commercials, which feature Green Mobile Man, a superhero who goes around saving people money. When he punches villains, a big "KA-POW" appears on the screen. "I knew that we had to do something really outlandish that would last in people's minds," he says.

Being a recognizable face on campus does have its downside, however. When, in 2007, Laoruangroch was arrested on suspicion of driving while intoxicated, the school paper covered the news. After the incident, Laoruangroch took an alcohol-awareness class and says he kept himself out of further trouble by partying less. "Anytime you slip, you have to get back up on your feet and keep on going," he says. "It's something that compares to business a lot."

This year, Laoruangroch expects sales to accelerate because of the recession. The company's pitch has always been convenience -- its slogan is "Change your phone, not your plan." But Green Mobile is well positioned to present itself as a low-cost alternative to other phone retailers. Fixing a phone means customers don't have buy a new one. And recycled phones run as low as $30 at Green Mobile; carriers typically charge $100 or more for a phone that is not bundled with a service contract.

Managing multiple locations will become a challenge. But Laoruangroch has found he has a knack for retail. For example, when Green Mobile opened its Kansas City location, it did so without a completed floor plan. Laoruangroch's thinking was that the store's layout would evolve around the workflow as it happened. "If you try to build the store before you're operating there, you don't really know what to expect or how to build it," he says. So far, the business has found that it's efficient to set up cabinet workstations in the front of the store instead of having to bring every repair to a work area in the back. The approach cuts down on the time it takes to complete a transaction and fosters interaction with customers, Laoruangroch says. He has since reorganized the Columbia location along the same lines.

As Laoruangroch's business has grown, he has found it difficult to juggle work and school. Now that he is working 60- to 80-hour weeks, Laoruangroch, who is nine credits shy of a diploma, is looking to finish his degree online. He confesses some nostalgia for the classroom, however. When he was getting Green Mobile off the ground, he says he found himself paying closer attention to his professors when they covered business fundamentals such as branding and marketing. "I was learning important business concepts while I was using them in my own business," he says. "I was genuinely more interested in what they were teaching."

He remains in touch with his professors. Some have chastised him for missing class to go to business meetings, but a few have invited him to speak to their classes.