Abel wrote:
The other day I was trying some fancy pronunciations for a couple  
(some not-so-fancy ones, too), only to be surprised by that fact that  
my /s/ and my /z/ sound quite noticeably different when I round my  
lips when
I pronounce them.

So, is there anything like rounded /s/ or /z/? I am hoping to use  
this as a
phonemical distinction in some conlang. And what would be a good  
symbol for
them? Perhaps, z-ring and s-ring? ;-)

Oh, yeah, tons of natlangs have them.  I think that's actually the
appropriate way to use the "w" diacritic in the IPA (different
from the consonant simply followed by "w").  I don't know
which English dialects it is, but several of them are supposed
to have [S_w] for "sh", but it certainly doesn't sound like "shw"
would (compare "schwa" and "shaw").

"A male love inevivi i'ala'i oku i ue pokulu'ume o heki a."
"No eternal reward will forgive us now for wasting the dawn."

-Jim Morrison