Lots more links:

SQL Where - How to use == != and other operators in SQL
Datetime in Postgres
Datatype Datetime in Postgres
Modules in Ruby - A tutorial
Ruby Talk on Modules - Need to call the mixin module with the module name and a dot, like CommonMethods.lala
The fine structure of the Milky Way - Think about that sometime: You live in a galaxy with billions of stars, perhaps a trillion stars.
Ruby on Rails documentation - Outertrack - An interesting API reference
Ruby API documentation - Also on Outertrack
Ruby on Rails Manual
Ruby Manual
RWB - RWB provides a performance/load testing framework for webservers. It allows a great deal of flexiblility in how tests are configured, run, and reported on.
It will get better - Agile programming
Web 2.0 and businesses
Test Driven Development News
Introduction to Test Driven Development (TDD)
Test Driven Development on Wikipedia
Test::Unit - Unit Testing with Ruby
Fixtures - A way to setup data for tests in Ruby on Rails
ActsAsTaggable Plugin for Ruby on Rails - Cool... Tagging in a plugin.
More ActsAsTaggable Plugin
Subversion Book
GeoRuby - Map plugin for Ruby on Rails with Postgres and MySQL
Ruby on Rails plugin list
ActionView::Base