My favorite of those is the Febreze Noticeables in Vanilla/Lavender scent. My hard-to-impress MIL noticed how pleasant and clean the scent was as soon as she walked in the door, which made me smile...and sigh in relief. It lasts a solid 5 weeks and is a nice, subtle scent.
However, these days I'm all about saving money and saving materials. So, I tried out a trick that I heard about on The Nest. I boiled some water on our stove and put in a few drops of an essential oil I had on hand. Our entire house smelled wonderful in no time.
I used Aveda's Peppermint oil but any scent will do. Cheap, easy and effective!