gistfile1.rb

class FieldType < ActiveRecord::Base
  has_many :model_object_types
  has_many :field_values
  attr_accessible :name
end

class FieldValue < ActiveRecord::Base
  has_one :field_type
  has_many :object_models
  attr_accessible :value
end

class ModelObjectType < ActiveRecord::Base
  has_many :object_models
  has_many :field_types
end

class ModelObject < ActiveRecord::Base
  belongs_to :model_object_type
  has_many :field_values

  def method_missing(method, *args, &block)
    field = self.model_object_type.field_types.detect { |f| f.name == method.to_s }
    if(field)
      self.field_values.where(:field_type_id => field.id).first.try(:get_value)
    else
      super
    end
  end

  def respond_to?
  # ???
  end

end