BMRT (Blue Moon Rendering Tools)
BMRT was discontinued and its
maker Exluna was bought out by NVIDIA.
There was a lawsuit and
settlement between Pixar Animation Studios and
Exluna over patent infringement. BMRT is no longer being supported or
available.
Here is a link describing the
lawsuit between Exluna and Pixar:
http://www.renderman.org/RMR/OtherLinks/blackSIGGRAPH.html
Pixar’s Renderman