variable-width font in summary buffer?

I'd like to use a variable-width font in my summary buffers, but it
seems that, especially when displaying threads, much of what Gnus does there
depends on a monospaced font.

Is anyone successfully using a variable-pitch font in the summary
buffer, and if so, do you have any configuration tips?

Thanks,

--

-- 
Dave Abrahams
BoostPro Computing
http://www.boostpro.com