something stupid w/ polymorphic associations

gistfile1.txt

class Deal < ActiveRecord::Base
  belongs_to :store
  has_many :categories, :as => :categorizable
end

class Store < ActiveRecord::Base
  has_many :deals
  has_many :coupons
  has_many :categories, :as => :categorizable
end

class Category < ActiveRecord::Base
  belongs_to :categorizable, :polymorphic => true
end

#I want to be able to given a certain category.name, get a list of Deals
#and then given a certain category.name, get a list of Coupons

create_table "categories", :force => true do |t|
t.string "name"
t.integer "categorizable_id"
t.string "categorizable_type"
t.datetime "created_at"
t.datetime "updated_at"
end