Like Shabby over-riding basically any identifiable information about someone at a glance, for example. I'd support this idea, but only if "Stinking" didn't over-write whatever existing data there is to be had about your character.
I think that after passing through at least two or three sewer exits, a character should have a "smells like shit" message appended to their desc. The sewer descriptions and messages are so well-written and themely in their disgustingness, so why can't our characters stink like they just crawled out of a giant puddle of shit?
It would also encourage more people to use Quick Kleens and other showers if they don't want chars to know that they were sewer-spelunking.