base_model.rb

class BaseModel < CouchRest::ExtendedDocument

  # I like nil instead of Exceptions when resources can not be found.
  def self.get(id)
    begin
      super
    rescue RestClient::ResourceNotFound
      nil
    end
  end
end

user.rb

class User < BaseModel
  # now User.get("bogus_id") returns nil - win!
  ...
end