My goodness, how far Google's come
Considering how large Google (the site) is now, with all the development work applied to the services subsidiary to the main search feature - image search, Google News, Froogle, Google Maps, GMail, Google Earth, I'm amazed that the whole thing started with a simple two-page search process. Certainly there were more files, scripts, pages and libraries within the site that no one ever saw, but I'm estimating that more than 99.9997% of the site's traffic was from (1) the homepage/search form, and (2) the search results page.
This makes for a feat nearly unbelievable and practically impossible to replicate these days. And yet it's the gold standard for the way so many things are done online.
I wrote in 2003 about the main reasons "the unassuming search engine with the world's simplest UI", and I still tip my cap to the way the site turned the Web completely around.