The Rails 3 template I use. Here's a list of gems:
mongoid (optional)
haml (+ haml_rails for generators)
compass
devise
cancan
rspec-rails (+ database_cleaner if using mongoid)
rr
factory_girl
metric_fu
Usage:
cd dev
git clone git@github.com:pigoz/rails-template.git
rails new my_application -T -O -m rails-template/template.rb # for mongo_id
rails new my_application -T -m rails-template/template.rb # for ar