Last week I came across interesting web site by Todd Hoff who was former IBM and Intuit Employee.
His site http://highscalability.com/ on high scalable architectures has some big shot web sites explaining lore, art and science behind it. Some examples are:
- YouTube Architecture
 - PlentyOfFish Architecture
 - Google Architecture
 - Flickr Architecture
 - Amazon Architecture
 - Scaling Twitter: Making Twitter 10000 Percent Faster
 - An Unorthodox Approach to Database Design : The Coming of the Shard