Funny you bring this up, because I was just recently thinking that one of the things I find interesting about cycling is being more in tune with what's around me based on smell (even though not all of those smells are pleasant).

I don't know that I've smelled anything that hasn't been mentioned. Stale water when I ride by the canals. Fast food when I ride near restaurants. I stay off the main roads, so don't smell a lot of exhaust. Sometimes I smell cologne but can't see anyone, which kind of creeps me out. Laundry, flowers/trees in bloom. When it's really hot the pavement has a smell...I think it's melting.