Weak and fickle. Usually the last sense organ to know about anything. The eyes see the smoke, the hands feel the heat, and about ten minutes later the nose smells a fire.
Tingles at strong perfume. Went through a phase of trying to force myself to like all smells, even the worst ones, in an effort to appreciate everything as a kind of beauty. It doesn't work. The worst smell I ever experienced was in Harvard Square when I was 16, it was a putrid urine scent mixed with a stinging alchohol-based bile. It was so sharp, I think my nose turned off permanently.
I don't smell things very well. I can't recognize my own scent but I always hope it is pleasant. When food comes out, I usually see it more than smell it. Some exceptions exist, of course, and happily: The smell of chai and masala teas, miso soup, warm skin, the chocolate factory near the cambridgeside galleria, my friends apartments (a mix of spray paint and vintage clothing).
If a drop of water runs from my hair down to the tip of my nose, my knees buckle. It's completely strange and 100% repeatable.