I know what you mean about fresh cut grass, that is a definite feel good smell. OK here are my favs:
Bandit's scent (bath or not)
The Sea
Lilacs
Fall leaves
Tea
MONEY
Roses
Niagara Falls (somewhat like the sea but different since it's fresh water)
Rain
Antique books
Interiors of antique cars
Candles on a cold night
Pine trees
French Fries at a carnival or outdoor dining place


Back to the smell. It made me think about some other smells that can alter a day you mood or your 'tude in general. Things like the smell of a bakery when you open the door. All those freshly baked products aromas combines into a delicious symphony for your schnozz. The smell of bacon cooking
Fills the whole place with a smell so good that you can actually taste it. Makes the eating of the bacon almost secondary to the smell. Cinnamon, especially first thing in the morning. Maybe some ooey gooey cinnamon rolls freshly baked right out of the oven.
The smell of a fresh pot of coffee does it for some. Kinda wakes 'em up more than the cafienne in that cup of java itself. Fresh baked bread, garlic, sausage, one of my personal favorites the smell of fresh basil or how about a hint of minty freshness!
That can always brighten up a day. The smell of the ocean or fresh fruit or veggies! Some prefer the smells they um uh "create" with their own body but that's usually not the case for those around them 
So what smells do it for you? What smells change your mood or your 'tude? Is there a certain smell that does it above all others? Do you like to smell your old dirty shoes? (I'll pass on the dirty shoes but please, feel free to have at it and knock yourself out if you must) What smell can turn a day around for you even when you're down? Whatever it is, on a day like today you might wanna sniffer you sniffer in that direction or at least just follow your nose until you find it to kinda chase away the blahs of a rainy day. Then again, you could just think about the smell of suntan lotion that is only a couple months away.

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