Most folks use Google as their default search engine and may be unaware that others exist. That's because, usually, Google delivers the best search results. The engine is so good that it's become a verb. Looking for someone or something? Google it. However, a new outcrop of search engines are set to challenge Google as the king of internet search. They'll have a hard time playing catch up, but they may be able to serve a narrower audience with more relevant results than Google. CNN does a nice round-up of these sites and discusses how they'll potentially impact web surfers in the future.