Links for smart kids:

memcached - I'm using it to store session data for Rails, but you can use it as an intermediary between your web application and databases. First developed for the livejournal.com website.
MemCached in the Ruby on Rails wiki
Using memcached for Ruby on Rails session storage
Download site for memcached-client - It's better to use the memcached-client-1.0.3 version, instead of the gem version, it's faster.
Improving Ruby on Rails performance
Namespaces and controllers and models, oh my.
How to change SessionStore in Ruby on Rails
The new Googleplex. I really like architecture.
How to change session options
mod_proxy_balancer
Introducing SwitchTower - Now called Capistrano.