A great thing about Coupa work is how I can hack it up without a network connection. The codebase is checked out and I run mysql locally. I fire up emacs and a script/server and I'm pretty much good to go. The only downside is not being able to access the rails and gems docs. Here's what I did to put together a productive local setup.
Update: 2009-03-30 Jason Seifer of RailsEnvy does a better job of explaining the process than I do.
Note: For the rest of this guide, I'm going to assume you have ruby and gem installed via MacPorts. If they aren't, change the directories in the commands appropriately.
First of all, let's generate the documentation for all of your gems. If you're more accustomed to the layout of Rails documentation, then install Jamis's rdoc template.
# this step is optional
cd /opt/local/lib/ruby/1.8/rdoc/generators/template/html
sudo mv html html.original.rb
sudo curl -o html.rb http://www.whatcodecraves.com/posts/2009/02/28/rails_and_gems_documentation_anywhere/rdoc_template.rb
(The link to the original template was broken for me.)
Now actually generate the rdocs.
sudo gem rdoc --all
After the command finishes, start a gem server so you can browse the docs:
gem server --daemon
Point your browser at the gem server.
You'll notice that no rdocs were generated for the Rails gem. This is because the rdoc task is intended to be run from the root of a frozen Rails app. This is amazingly annoying, but is a solved problem. Basically, you have to freeze Rails in your app, rdoc it, unfreeze it, and copy over the rdocs.
cd myapp
rake rails:freeze:gems
rake doc:rails
rake rails:unfreeze
sudo cp -R doc/api/ /opt/local/lib/ruby/gems/1.8/doc/rails-2.1.1/rdoc/
Now you can code from anywhere! As an added bonus, the docs will load blazingly fast.