Sweat trickling down one's back.
Not being able to wear contact lenses. Fine half the time, because my brain's adaptable like that- read with left eye, see distances with right. But brain has a way of suddenly wanting to use both eyes simultaneously and frets until it can.
The sensation at night of tiny insects batting about one's arms and into one's hair and, worse, nose.
The tiny insects that do bat about- fruit flies that seem to breed from air, no matter how scrupulously one cleans the kitchen.
The film of grunge on one's skin always- sweat and air pollution.
The unspeakable stuff one blows into tissues and hacks up from the lungs, and the even worse stuff that emerges with saline rinse. OTOH how lovely to have all that out of one's body so easily.
Trying to make do with fans because AC turns the rest of the house into a hot sodden towel. But fans don't quite do, and moving air feels cold but using a cover makes you hot, etc etc etc.