A fast, accurate real-time GPU renderer for only about $110!
Sunflow Render System:
A gorgeous GI renderer – free!
An awesome physically based and unbiased rendering engine that plugs into almost all the major 3D packages.
A beautiful, high quality renderer, free and open source.
This proprietary real-time renderer plugs in to Blender, Revit, Sketchup, Cinema4D, Max and Maya.