Zac Workman became a connoisseur of energy drinks at an early age. At the end of each day, after five hours' practice for his high school swim team, he would choke one down. His drink of choice "tasted awful, but it gave me energy, so I just kept drinking it," he says. Today, the 21-year-old junior at Indiana University is the founder of ZW Enterprises, which sells its own energy drink, Punch.

After completing his freshman year, Workman threw himself into researching energy drinks. He identified what he saw as an unfilled gap in the market -- an energy drink that was made from natural ingredients and did not produce the crash effect common with sugary or highly caffeinated beverages. Working with a fruit-punch recipe that has been in his family for years, Workman came up with a drink that tasted good and satisfied the necessary dietary requirements. He began to pitch it to potential manufacturing partners. After a slew of dead ends, Workman found Power Brands, a Los Angeles–based beverage development firm whose clients have included Gatorade, Pepsi, and Sierra Mist. Executives there agreed to meet with the student -- if he flew to L.A. "I wasn't sure it was something my parents would support," Workman says, "but they said yes and decided to make it a family trip."

Power Brands CEO Darin Ezra says his team was impressed by the professionalism of Workman's research and presentation. Then there was Grandma's recipe. "The taste of Punch was definitely a major component in why we decided to work with Zac," Ezra says. "One of our project managers rated Punch as her favorite product of 2008, which is great, considering we developed over 250 products last year."

Within days of signing a contract with Power Brands, Workman began collaborating with chemists to develop a drink that could be mass-produced but that did not contain high fructose corn syrup, sodium, or preservatives. After 10 attempts, the recipe was finalized. Workman and his family put up $200,000 in start-up capital.

Since Workman launched Punch last year, three Anheuser-Busch distributors have picked up the product; they sell it in most of Indiana and Illinois. To get the word out, ZW Enterprises is co-sponsoring a car that will race in the Indianapolis 500 in May. Sales are on track to reach $1 million in 2009. The black-and-red can is his design.

Running a business on campus has been surprisingly easy. "People would think it would be difficult to balance class and a business, but I'm learning more now than I ever have in the classroom," says Workman, a finance and entrepreneurship major. "Because now, I'm sitting in class learning business strategies meant to be applied in the professional world, but I actually get to do that when I go home."

Workman's professors have been extremely supportive. "I have a management team worth several million, and they work for free just to see me succeed," he says, adding that his classmates have embraced Punch, too. "I come home at least once a week to find money on my bed from a friend who wanted a Punch and took it from the fridge," he says.