The best way to utilize every drop of goodness is to stick your nearly empty bottle(s) in Epsom salt and let the salt draw out the remaining oil. I'll then use the oil laden salt in my (or my son's) bath!
Chemical Free Air Freshener In a 3 oz. glass spray bottle add: 10 drops Lemon and 1 drops Purification Essential Oil. The lemon smell wonderful, and the purification kills airborne microorganisms and odor.