Slug/Permalink using Rails 3 Concern

Post.rb

# example (untested)

class Post
  include Slugged
end

post.create :title=>'Great Gist'
post.slug == 'great-gist' # true

slugged.rb

# stringex gem in Gemfile
# "slug" and "title" attributes in models where you want slugs
# t.column "title", :string
# t.column "slug", :string

module Slugged
  extend ActiveSupport::Concern

  included do
    before_save :slugify
  end

  def slugify
    self.slug = self.title.to_url # to_url is provided by stringex gem.
  end

end