Here's a company that is smart enough to know that they could have a major part of a market though could explode. Google don't just have to sell ads. They have loads of very smart people. They could wind up being the major provide for driverless cars.

Sebastian Thrun works for Google now. He's one of the world's foremost experts in the field.

"They could wind up being the major provide for driverless cars."

I'd say they could be the major provider for driverless car technology. I don't think they should get into actual car manufacturing.

Bingo, this is going to be a big field in the future. AI is outside the core competency of car manufacturers; they'll have to buy that tech from some one. Google's ad revenue could look puny by comparison some day.

This sounds like the history of a company out of a Stephenson or Gibson book. I want to believe...

Indeed. This is what I meant.

This could also be part of Google looking for revenue sources beyond advertising. As other commenter have pointed out, if Google can make this work and smooth out the very non-trivial legislative and liability issues, there's an absolute fortune to be made licensing this technology to car companies. Think about it. If the technology works, and it's legal in your state, do you know anyone who wouldn't want a self-driving car?! It would revolutionize commuting. You could nap, read, watch TV on your phone or tablet, etc. instead of staring in boredom at the bumper ahead of you.

They probably build robot cars because they are an artificial intelligence company.

Yes. They probably can make quite some money by patenting that tech and licensing the components to car makers.

Why be so cynical? Here is a company that has found such a massive golden egg that at least for now it can hire really really smart people to work on cool projects that may end up changing the world.

I think they just like playing with stuff that is this cool. It's great that it aligns with their business model, but I don't think the thought process went "hey, let's build a driverless car so people can see look at ads more!"

It's also a good recruitment tool having a couple of world-class people working on stuff that interests a lot of computer science types.

No, they are building robot cars because

1) They can sell them (the market is enormous)

2) It's fun and interesting

3) Great for the overall company image (as innovators)