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.

As an investor, what we're not looking for is 'oh this is a cool app,' it's 'is this something that can become a big business?' You need to find those that can become real businesses.

When radio stations started playing music the record companies started suing radio stations. They thought now that people could listen to music for free, who would want to buy a record in a record shop? But I think we all agree that radio stations are good stuff.

They also can combine voice with instant messaging and online file sharing.

The next Google or Facebook will come from somewhere other than Silicon Valley.

When we look at investing, we always think about 'how defensible is this, how likely is it that somebody is going to copy this.' E-commerce tends to be something easy to copy because it's execution.

Angry Birds is one of the fastest-growing online products I've seen, growing even faster than Skype, and the company has done a brilliant job of extending it across different platforms and merchandise.