Great question.
I have many smells I enjoy, not necessarily a single one, but for various reasons of nostalgia, or pleasure, they resonate with me:
flower fragrances, in particular lilac and honey suckle
gasoline;
musk,
woods,
cedar,
a forest,
apple pie,
bread baking,
chocolate chip cookies out of the oven,
musk
my skin when the sun soaks into it,
coconut suntan lotion,
the ocean,
fresh cut grass,
my late husband's cologne,
baby lotion...