Kerkythea is a freeware rendering system that supports raytracing. Currently, it can be integrated with 3ds Max, Blender, SketchUp, Silo and Wings3D (generally any software that can export files in obj and 3ds formats). Kerkythea is a standalone renderer, using physically accurate materials and lighting. Binary only distribution for x86.
Component -> New packages? Upstream looks to still be active.