http://www.3dvirtualight.com/download.html
http://www.3dvirtualight.com

VIRTUALIGHT is Stephane Marty's sophisticated standalone rendering engine that allows previewing and photorealistic rendering of 3D scenes. Like the RenderMan Interface® from Pixar, its interface may be thought of as a 3D scene description format (this interface is not Renderman compliant). It can be used as a communication protocol between any modeling programs or production packages and the VIRTUALIGHT renderer to produce photorealistic quality images.VIRTUALIGHT is freeware and distributed with several utilities that allow data conversion from other 3D geometry file formats to the VirtuaLight Interface Bytestream.

The new one will be "VirtuaLight A.E.R.E" (for Advanced Experimental Rendering Engine).
The good news is that it will offer some of the most advanced rendering features ever (such as CIE XYZ color space, HDRI input and output, Metropolis Light Transport, Spectral Photon Mapping, Advanced surface materials, Multi-threading, etc.),
The bad new is that it won’t be compatible with VirtuaLight old” generation (such as version 1.4) because of its new open architecture. Another reason is that VLight has several internal limitations.
Anyway, a first beta release should be available by the end of year. Some of the first tests will be published on this site quite soon.
Last info, “VirtuaLight AERE” will be completely freeware and available for Windows and Linux