Female users are the unsung heroines behind the most engaging, fastest growing, and most valuable consumer Internet and e-commerce companies.

If you're looking to grow your user base, is there a best way to cost-effectively attract valuable users? I'm increasingly convinced the best way is by harnessing a concept called social proof, a relatively untapped gold mine in the age of the social web.

Some investors may grumble about entrepreneurs wanting 'unicorn valuations.' But let's be honest: most investors want them, too, and are supporting the massive capitalization of these companies.

Especially when it comes to social and shopping, women rule the Internet.

Starting a company and being a founder is really hard, and most companies fail. You really have to have a deep commitment and belief in it and be willing to see it through many ups and downs.

Companies that are growing the fastest are the ones that are the most fanatical about costs, ... We've got the machine working on 6.5 out of eight cylinders.