DD30 and DH each have signature "smells." It's not the smell of perfume or after shave, or even skin cream. Both have their own smell but I can always tell which pillow is DH's, which blankie DD has been using in the living room. It always makes me smile, and brings me comfort.
The smell of onions, peppers, and garlic sauteeing in the kitchen. Love this, it's the comfort smell of home.
Lilacs... they remind me of my mom.
Honorable mention to the smells of Disney, especially the smell in Spaceship Earth at the start of the Dark Ages, when Rome is burning. Also the smell of the orange groves in the original Soarin'.