list of free renderers

List of free render engines :

Freeware multi-platform ray-tracing package. Include software download
offical website

Yaf(a)Ray 0.1.0 is a new raytracing render engine written from scratch, and it replaces YafRay 0.0.9. After two years of development, it already features a complete set of lighting and rendering options NOTE ITS MADE FOR BLENDER3d.
offical website

some more that supports blonder :
Kerkythea
Site: offical website
Last Update: 2/16/06, version 1.3.01
OS: Windows, Linux
64-bit available?: No
Multi-thread available?: No
Blender export script?: Yes, downloadable from site.
Notes: XML scene configuration, stand-alone application

Sunflow
Site: offical website
Last Update: 2/26/06, version 0.05.5
OS: OS Independent
64-bit available?: Yes (if JDK is 64-bit)
Multi-thread available?: Yes
Blender export script?: Yes, downloadable from site.
Notes: Completely written in Java, open source

Indigo
Site: offical website
Last Update: 2/25/06, version 0.3
OS: Windows
64-bit available?: No
Multi-thread available?: No
Blender export script?: Yes, downloadable from site.
Notes: XML scene format, unbiased raytracer, code available

3Delight
Site: offical website
Last Update: 2/17/06, version 5.0
OS: Windows, Linux, Mac
64-bit available?: No
Multi-thread available?: Yes
Blender export script?: In development on elysiun
Notes: Renderman-compliant, campatable with Dr. Queue and BORG GUI, free for non-commercial use, extensive user manual.

Metropolight
Site: offical website
Last Update: 8/23/05, version 0.6.0
OS: Windows
64-bit available?: No
Multi-thread available?: No
Blender export script?: Yes, on elysiun.
Notes: ASCII file format

For 3ds max :

Brazil r/s is a high-quality photorealistic rendering system, created by SplutterFish, capable of fast ray tracing and global illumination Used in films like star wars revenge of the sith
offical website

BusyRay is renderer for busy people.
There is just one physically accurate solution possible per scene. Just press 'Render' and see how it looks like. No parameters tuning is needed.
offical website

CLICK-VR VISUALIZER
Click-VR Visualizer - for 3ds Max The premier real time rendering plugin for Autodesk 3ds Max! Instantly explore your scenes in real time and create lighting and realistic look and pan around in real time!
offical website

finalRender is a raytracing graphics rendering engine developed by Cebas Computer GmbH for Autodesk Media and Entertainment's 3D Studio Max and Maya software. A finalRender Stage-2 version for Maxon's Cinema 4D started shipment in late 2005.
offical website

fryrender is the unbiased spectral renderer developed by RandomControl.
All the elements involved in the render (materials, lights, cameras, ...) are based on physically accurate models up to the point that when you hit render a simulation of the real behavior of light happens inside.
offical website

[Discontinued] Luminaire Tools is a complete open source version of the Luminaire Global Illumination Tools plug-in set for Discrete's 3DSMax. This is intended to promote further development of the Luminaire Tools; to provide a usefull set of lighting DISCONTINUED!
offical website

Maxwell Render is the best render engine to create photorealistic images for 3D, simulation, architecture, productions... It is unbiased, using multilight
VERY PROFESSIONAL!
offical website

Mental ray is included in 3ds max but sometimes you will have to get hotfixes
and updates make sure you check autodesk web site for updates
offical website

Vray one of the most popular and most used 3d render engine for 3ds max
very fast and efficient and easy to use it has very advance facilities
offical website

VoxelRender Project Closed )):
offical website

some more that are dead ))))))): i am so sad i couldn't try all of them:
AF Render [dead]
The Atmospheric Engine [dead]
Entropy [dead]
Insight [dead]
Jackie [dead?]
RadioRay [dead]
Raygun [dead]
RayStudio [dead]
RenderP3D [dead]
MaxMan [dead]
VLightMAX [dead (VirtuaLight no longer available stand-alone, integrated into trueSpace), exporter]

to get the whole list of 3d render engines click on the link below
it has hundreds of 3d render engines you that will get you lost

http://www.pointzero.nl/renderers/