Aaron Patzer, Founder of Mint.com

Aaron Patzer, 29 

Founder of Mint.com, a free online financial planning website.

At the age of 25, Aaron Patzer had master's degrees in computer science and engineering from Princeton, but still had a hell of a time doing his banking and budgeting online. He struggled to get quick answers to simple questions about his finances like "How much money did I spend this month?" Realizing he couldn't be the only one with this problem, Patzer started Mint.com in 2007, which he sold to Intuit for $170 million in 2009. "When I started Mint.com," he says, "I worked seven months alone in a room, seven days a week. Whenever I felt doubt, I listened to 'That's Life' by Frank Sinatra, or read my favorite Shakespeare quote: 'Our doubts are traitors, and make us lose the good we might oft win, by fearing to attempt.'"

What Drives Patzer?

"Building a product to solve a real problem. There are tens of millions of people using online banking who can benefit from having a single, aggregated look at their spending."

Don't Just Call Him an "Entrepreneur"

"I consider myself an inventor first and an entrepreneur second."

Who Taught Patzer About Business?

"I credit my parents. My dad read me the Wall Street Journal when I was a toddler; my mother taught home economics. My dad taught me about compound interest, which changed the way I thought about finances."

But His Parents Did Give Him Some Bad Advice

"To stay in my Ph.D. program."

Patzer's Number One Hero

"Thomas Edison, because he not only was an incredibly prolific inventor, but also successfully got his inventions out to help the public."

The Scariest Moment of His Entrepreneurial Life?

"After working on the product for nine months, having a competitor launch 11 months before we were ready."

The Most Inspirational Book He's Read

"The Fountainhead by Ayn Rand. It's the essence of the individual creative spirit in creating all value in the world."

The Technology Patzer Can't Live Without

"Skype. My girlfriend is overseas right now."

His Best Advice to Those Who Want to Start Businesses?

"Stone cold, iron-willed determination. It's going to be long hours and a lot of hard work, but if you have confidence in your product, you will succeed."

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