Niklas Zennstrom

If you want to be an entrepreneur, it's not a job, it's a lifestyle. It defines you. Forget about vacations, about going home at 6 pm - last thing at night you'll send emails, first thing in the morning you'll read emails, and you'll wake up in the middle of the night. But it's hugely rewarding as you're fulfilling something for yourself.

As a kid, I always idolized entrepreneurs. I thought they were cool people in the way that I thought basketball players were cool people. It's cool that some people get paid to dunk basketballs, but I'm not one of those people.