RhinoMan works well with these renderers:

Pixar's PhotoRealistic RenderMan High-quality renderer used in many movies

3Delight (free renderer, some features still under development)

AIR (low cost and well integrated with RhinoMan)

Aqsis (free renderer, some features still under development)

Some other useful links:

Rhino3d http://www.rhino3d.com

The Renderman Repository http://www.renderman.org/

RenderMania  - rendering info

Renderosity - graphics artists community

comp.graphics.rendering.renderman RenderMan USENET group

eGroups BMRT discussion

Shader writing tutorial and information