Dropbox is useful to anyone with a phone. That's, like, two billion people.

With something like Dropbox, it was immediately like, 'Wow, this is literally something that anyone with an Internet connection could use.' Everyone needs something like this; they just don't realize it yet.

People do not choose Dropbox because it has this much space or gigabytes. They choose it for the experience.

A lot of really great, innovative things have happened when people just didn't know it wasn't supposed to be possible.

People make basic assumptions based on what they have now. But you have to ask yourself, 'Is this really what people are going to be doing in five years?' Very few people ask themselves what they would actually want instead if they could wave a magic wand.

When I think about it, the happiest and most successful people I know don't just love what they do, they're obsessed with solving something that matters to them. They remind me of a dog chasing a tennis ball: Their eyes go a little crazy, the leash snaps and they go bounding off, plowing through whatever gets in the way.