Saphira likes to sniff stuff that is unknown to her, when I had brought home Nico&Anya's window bench from our other house she immediately went crazy over it--sniff! Sniff! Sniiiiiiiiff!! Why? Probably because its new to her. I guess the smell of cat, dog, and new people smells nice to her.
So that begs the question, does your cat do this too? What is his or her favorite things to sniff?