Smart CPM is a pricing model which will help you to save budget. It is based on CPM (cost per mille) but has one important benefit.
Smart CPM uses a special algorithm that looks for the opportunity to buy traffic for you cheaper. Your bid becomes the maximum allowable bid in an auction for displaying ads. The Smart CPM algorithm will evaluate the bid for your target and will make the lowest possible bid for your victory.
Smart CPM is currently available for Popunder in Clickadilla.