#2: Cat Litter.
Have a smelly closet or musty basement? Set out a tray of cat litter, specifically, Jonny Cat Litter brand, recommends Joey Green of Joey Green's Cleaning Magic (Rodale, 2010). One primary reason that brand works so well has to do with the fact that the main ingredient is diatomaceous earth, a naturally occurring mineral that, among its many wonders, absorbs odors (it also absorbs moisture in the air, and kills pests that come in contact with it). So if you can't find any Jonny Cat Litter, buy a box of diatomaceous earth and set a few bowls out in the corners of smelly rooms. You can find it online from garden supply stores, such as Planet Natural.