Starting with the worst--

1- Smoking, the smell of people smoking, dropped lit ciggeretes that have not been put out in parking lots, ect. Also, the fumes put off be ciggerettes that people smoke half of and try to save to finish later.

2- Tobacco residue, This includes chewing tobacco, the spitting from it both on the ground and into a container, those who make, roll their own ciggeretes, the tobacco ilse at a local supermarket, yes even checking out in that line near it bothers me, I'll wait in a much longer line further away from it.

3- Vomit, the smell of vomit is pretty bad, when you have to clean it up, and it almost make you yourself vomit.

4- Dogs, the smell of those with dogs or pets that stink up their house. They don't smell it because they are used to it.

5- Roadkill, the smell of the dead.

6- Rotten food, or drink, milk, juice.

7- those stink bugs, when you smash, kill them they put off an oder.

thats all that comes to mind.