I attended a talk yesterday where Luiz André Barrozo, from Google, offered a technical overview of how Google works. It wasn't too much detailed but very interesting. He explained, for instance, they are so focused in robustness and efficiency that they have written all their software, but some small and controlled fraction of Linux. As far as it seemed, that includes web servers, indexes, network communication (based in HTTP, TCP and UDP), load balancing, and so on. He said they program mainly in C/C++, there is some Java as well, and a lot of Perl and Python scripting.

It seems they radically avoid any fancy things that aren't necessary, and this comprises from interface design to hardware choices. I love that attitude. I had the impression that they have clear, well-defined goals and a pragmatic and effective way to accomplish them.