Postural drainage, and changing posture to permit gravity to aid in moving mucous out of different portions of the lung assists as well.
For the really tenacious mucous, laying on the stomach with a pillow at the base of the rib cage can help, as the patient's body weight helps compress the diaphragm and add force to the cough, helping push the nasty gunk out.
All are 'tricks' I have used with good effect in the past.
Thieves Oil, which you can make yourself, has eucalyptus in it.
I am going to make a batch of it up and diffuse it in the air. I am going to try Eucalyptus radiata. You can rub thieves oil on the soles of your feet - supposedly it gets into your system faster that way.
I don’t know much about herbs and such. But the nastiness of this swine flu has made me think outside the box.