Look for when the environment is changing - the big shift now is mobile Internet. It's really happening big-time. The way you interact with services on a smart phone compared to the Web is quite different, so there's a huge opportunity.

People need to access Skype wirelessly, no matter where they are, and what happens is that we'll be taking advantage of the rollout of Internet everywhere - WiFi and WiMax in particular.

When we started Skype, if you look at analyst reports, no one forecasted it as a big business. Also when Google started, it was not fashionable to be in search. It's not trying to do the obvious - that's the hard part.

We have 2 million users in the U.S. and about 13 million worldwide in more than 200 countries. We're getting 80,000 new users each day. And more than half a million people are connected via Skype at any given moment.

With our work at Kazaa, we began seeing growing broadband connections and more powerful computers and more streaming multimedia, and we saw that the traditional way of communicating by phone no longer made a lot of sense.

Then people started using it more and more and it became the most downloaded software on the internet.

Silicon Valley is the best place to start a tech company in so many ways.