maya and displacement maps
after days of fighting with this (countless crashes thanks to a somewhat lacking integration of mental ray) I finally had a little breakthrough yesterday.
note that this head is a pure poly model with just under 5000 polys (I tried with SubDs before, but that only crashed... I already logged that bug with Alias). I used the mental ray displacement approximation to tesselate it at rendertime to allow for all the fine detail.
here's the screenshot: