I agree with a couple of previous posts.  Avgas would be a great one as well as Airshow.  It could be a combination of smoked turkey legs, airshow smoke, babes wearin sunscreen and sweat.  Plus you would have the great smell of the warbirds in there.  Another scent that I always liked, was burnt RC aircraft gas.  That hint of oil and burnt fuel is awesome.  Would tick of the wifey, but who cares.