Cuil. On a serious note, it seems to me that barrier to entry for search is now exponentially higher than it was when they started. I'm not sure if it's even doable with small resources (in proverbial garage) anymore.
Probably not in the sense of the standard Google plays in now being very close to natural-language awareness. You can probably garage up a Webcrawler or a Lycos relatively cheaply, but it's going to feel clunky and complicated relative to the queries Google and Bing can support.
I keep mentioning "restaurants near me" in this thread because it's absolutely killer that's possible now.
I dont know how much money MS do with Bing, but if i were they, i would open source everything to see a lot of Google competitors pop here and there based on their tech, and later buy the most proeminent contenders.
They are locked in to the 2% position, and thats the only alternative i can see to shake things up and have a change to grab more.
They could also provide the pure search index for other companies by using their cloud infra, and charge for the cloud use instead where Bing would be only one of the clients of this open search index.
It was basically the strategy the open source world with the lead of Linux did to them, and were able to take down their dominant monopolistic position over software.
Because of having 90% of the search engine market they have a uniquely comprehensive view into the human mind. I would not be suprised if these huge data aggregation companies lead the race into sentient AI.
I feel like by now Google has enough dirt on anyone to personally ruin them. "Well, why did you look up 'Can you die from eating too much hair?' in 2012?"
If you've got your history enabled (which it is by default -- https://myactivity.google.com), you'll discover how much insight it actually has into your mind.
"Cat videos" and "good restaurants" is not all that people search for.
Who has the other 8%?