This gem generates a URL slug/permalink based on fields in a Mongoid model.
class Book
include Mongoid::Document
include Mongoid::Slug
field :title
slug :title
end
>> book = Book.create(:title => "A Thousand Plateaus")
>> book.to_param
"a-thousand-plateaus"
>> book.update_attributes(:title => "Anti Oedipus")
>> book.to_param
"anti-oedipus"
>> Book.find_by_slug("anti-oedipus")
#<Book _id: 4c23b1f7faa4a7479a000009, slug: "anti-oedipus", title: "Anti Oedipus">