Before Mint.com, I was a long-time user of 'Microsoft Money' and Intuit's 'Quicken.' Both were powerful tools, loaded with features and functionality around taxes, investment, budgeting - too feature-laden, in fact. They took hours to set up, forever to learn, and an hour a week to maintain.

The original idea before Mint was a life and goal planning system I called Carpe Viva. The idea was that all of life's goals, from buying a house, getting an MBA, or learning Spanish could be quantified in both time and money.

Carefully calculate the potential size of your market to make sure you can grow. Before starting Mint, I knew that there were about 20 million people who had purchased 'Quicken' or 'Microsoft Money' over the years, and 80 million people using online banking in the U.S. alone.

I always knew I wanted to be a technologist, so I went to Duke and got a degree in computer science and electrical engineering. Really, I thought my goal in life was to be an inventor, a problem solver, so I thought I needed a Ph.D. to be good at inventions, but it turns out that you don't.

Social media makes you think.

There's a new set of transformative technologies such as machine learning, AI, and virtual reality that will spawn another set of big tech franchises. But in terms of cultural impact, perhaps we are at peak Valley.

I work a lot on skill demands and changes in labor markets having to do with technology and with trade as well.

Even though I'm totally dependent on modern electronic gizmos, from my laptop to my iPod to my cell phone, I love to embrace old technology or no technology at all.