I remember reading articles 1998/1999 saying that the search problem had been solved and no major new search engines would enter the market.

Google proved that wrong.

There are many 1+ billion opportunities. Think of the ideas that started Google / Facebook - Pagerank and a class hand-book. Had these ideas been explained to me as starting successful billion dollar companies, I would have laughed.

Not to say that that all laughable ideas create billion dollar companies. However, I think the laughable part is the interesting bit. Maybe we find these ideas humorous because they force us to look at the world in a different way.