The NY Times has an interesting article about Google and its core business - the search engine.

It gives some insight on how Google constantly tweaks the search ranking algorithms and why.

Quote from the article:
"At the top of a bright chartreuse staircase in Building 43 is the office that Mr. Singhal shares with three other top engineers. It is littered with plastic light sabers, foam swords and Nerf guns.
A big white board near Mr. Singhal’s desk is scrawled with graphs, queries and bits of multicolored mathematical algorithms. Complaints from users about searches gone awry are also scrawled on the board."
Read the full story on the NY Times.