There are so many "niche" businesses out there - that will be enough to bring in millions in revenue - simply because there is such a variety in what people want and need. And we'll never hear of them unless our interests happen to coincide with that particular niche.

Case in point - I've just started working for a company that is an upstart small player in the area of document management for construction companies. You'd think document management was a solved problem and there wouldn't be room for specialists in that area - but no, there are several multi-million dollar businesses that do nothing but. And there's still room for small companies like ours to grow into.