Lots more links:

Validations in Ruby on Rails
GPS course plotting with Google Maps and Linux
Hacking Google Maps
Neat web apps that use Google Maps
Pairins Wine and Microformats - Some of the work they are doing with microformats of XML on the corkd.com website
Storing dates in a database
Pwning Second Life
How to Test ActionMailers and Controllers
ActionMailer and ActionController interactions
How to test ActionMailer in Ruby on Rails
RoR manual talking about ActionMailer testing
Testing Controllers
RoR extensions to the Time class
Mixing in class methods in Ruby
Assertions in Ruby on Rails
PostGres vs MySQL in Ruby on Rails
Tests in RoR
Funky new things you can do with Emacs 22
The power of Prototype.js
Design Patterns
Designing Tag Clouds
Performance benchmark a web server
AJAX edit in place with Prototype.js
Not your old GRASS anymore - Open Source Geographic Information System
Advances in GIS in Canada
Object oriented Javascript
RoR at Apple
Rails 1.1 cheatsheet
Ruby on Rails Associations - Difficult topic, partly because :belongs_to and :has_one are poor choices of names for these relationships.
More has_one and belongs_to problems
RoR model conventions
Ruby on Rails belongs_to
High Performance WebBrick - Server for RoR
Robot Co-op libraries
Robot Co-op tools
Wikipedia definition of a Closure in programming languages
gmail keys
XHTML media types