People take "spore showers" in Peter F. Hamilton's Void Trilogy quite often.
How exactly do they work?
Spore Showers seem to work like conventional showers but instead of water, they dispense dry spores held in a powder. The user rubs themselves with them, then uses jets of air blow them off.
"Her u-shadow told her when it was eleven o’clock, which barely gave her enough time for a spore shower in the fourth apartment where she was living. Two of the old shower’s five nozzles weren’t working, and one of the remaining jets smelt funny"
The spores are described as being "squirted" from the fixtures:
After the shower had squirted dermal fresher spores over him, he walked through into the vast lounge, bronze sunlight washing warmly across his tingling skin.
The spores cause:
a slight tingle on the skin
The spores come out of the nozzles at differing temperatures, at the control of the user:
So he turned the spore temperature down about as low as it would go, and thought of other things.
The spores seems to be dry, rather than held in suspension:
Then there was a shower—none of that modern itchy spore crap that clogged up his hair but a proper hot water and scented gel affair.
The spores can be used in conjunction with water or on their own:
“Good.” He stretched and rolled his shoulders. “Give me a shower,” he told the smartcore. “Start with water; shift to spores when I tell you.” ... After the spores cleaned and dried his skin he dressed in a simple dark purple one-piece suit
The spores themselves may be a derivative of the waxy 'sporecones' seen in the second book in the series;
They made camp that third day under overhanging branches which dripped an unpleasant waxy sap from their newly budded scarlet sporecones.
Overall the concept seems to be extremely similar to the "powder shower" seen in the film Tank Girl, albeit with an active (biological) cleaning agent rather than merely using abrasive dust.