We already know the wonders of bicarb soda when it comes to cleaning and deodorising. You can take this freshening power to any room of the house with nothing more than a crockpot and water.
The always creative blog One Good Thing by Jillee points out that you can naturally freshen any smelly room by filling a crockpot half full of water, sprinkling in a few tablespoons of bicarb soda, and then turning it on low (with the lid off). It will take a couple of hours to do its thing, so tuck it away in the corner of the room. I used this trick just this weekend to take care of a musty room, and it made a big difference.
13 NATURAL WAYS TO KEEP YOUR HOUSE SMELLING FRESH [One Good Thing by Jillee]