Mason jar air freshener - fill a small mason jar about 1/4 full with baking soda, and add 6-8 drops of your favorite essential oil. Punch holes in the lid, and place in any spot that could use some freshening. Every once in a while, give the jar a gentle shake to boost it's air freshening power.
My grandma taught me this many years ago. Refreshing towels I use this trick all the time since I noticed my towels smelling funky. It works! - Over time, towels build up detergent and fabric softener, leaving them unable to absorb as much water and smelly. Recharge them by washing them once with hot water and 1cup vinegar, then a 2nd time with hot water and half cup baking soda. This strips the residue and leaves them fresh and able to absorb more water again. Works like a charm!