So I seem to have acquired a permanent smoky effect that makes it damn near impossible to use a bow effectively on my first run as a pure rogueish archer type.

Is there a quest, or a mod, or some reason that this might happen? Or is it like the glitch I've gotten in a vanilla play that makes you shoot permanently shoot steam out of every orifice like a centurion? That one took like an hour and a half of guessing effect codes and console toggling them on and off iirc.

To fix it I tried:

Stripping myself naked in case it was caused by something I was wearing
Tried that in-game too.
toggled off all gfx options
Various save/quit/reload/cell move tricks that have worked for other glitchy things in the past
sixChange stops it for several seconds.

No dice.

Looks like this:
http://imgur.com/esx97,OLcNo,5yD6G,...ozr,dp4IE,Ik5l0

Smoke permanently obscuring vision. Wheeeee.

Photo link isn't working for me,

Is it like the effect in http://www.youtube.com/watch?v=ALsg0Ez3skM ?

There are some suggestions in the comments that might do the trick.

Similar but more obscuring.

This gallery should work:
http://imgur.com/a/M233o

Dunno why the first one expired so quickly,

Okey dokey then - http://skyrimforums.org/threads/smoke-effect-on-character-need-help.16179/ covers a problem similar to yours.

Thanks man! I'll give that a swing.
Makes sense, at least the strange kind of sense of Skyrim glitches. I had found my first wispmother right before this started.
I encounter a centurion and then 'catch' the steam eruption effect.
I encounter my first wispmother and catch her smoke effect.

Why does this stuff happen?

Not sure - in 600+ hours my characters haven't managed to catch anything like steam jets, smokey swirls or ghostly auras.

Though one character did experience a rather nasty case of oxygen deprivation, while viewing the Throat of the world from above, courtesy of a giants' club....