Changing furnace filters monthly is highly recommended to keep systems working properly. But who likes paying for those air filters? Not us, that's for sure! Well, we found a deal at Home Depot on their NaturalAire furnace filters that brings them in as low as $1.34 each when a case of 12 is purchased. It's actually possible to save up to 60% on these filters depending on the size and style needed. Order soon, this deal is happening only on 09/04/2014.